United States v. David Ming Pon ( 2020 )


Menu:
  •          Case: 17-11455   Date Filed: 06/29/2020   Page: 1 of 89
    [PUBLISH]
    IN THE UNITED STATES COURT OF APPEALS
    FOR THE ELEVENTH CIRCUIT
    ________________________
    No. 17-11455
    ________________________
    D.C. Docket No. 3:14-cr-00075-BJD-PDB-1
    UNITED STATES OF AMERICA,
    Plaintiff-Appellee,
    versus
    DAVID MING PON,
    Defendant-Appellant.
    ________________________
    Appeal from the United States District Court
    for the Middle District of Florida
    ________________________
    (June 29, 2020)
    Case: 17-11455        Date Filed: 06/29/2020       Page: 2 of 89
    Before ED CARNES, MARTIN, and ROGERS,* Circuit Judges.
    CARNES, Circuit Judge:
    A jury found David Pon guilty of twenty counts of health care fraud, in
    violation of 
    18 U.S.C. § 1347
    , and the district court entered a judgment of
    conviction on the verdict. After finding that Pon’s fraud scheme resulted in a loss
    of nearly $7 million, the court sentenced him to 121 months in prison. He appeals
    his convictions and sentence.
    I. FACTS
    Pon was an ophthalmologist.1 As a sole practitioner, he established his
    practice with a main office in Leesburg, Florida, and a satellite office in Orlando.
    Many of his patients were elderly. He diagnosed hundreds of them with, and
    lasered their eyes to purportedly treat, a debilitating and uncurable eye disease
    known as wet age-related macular degeneration (WMD).
    Here is how his scheme worked. Pon would run diagnostic tests on a
    patient. After diagnosing the patient with WMD, he would move on to the
    “treatment” phase, which involved lasering one or both of the patient’s eyes. Pon
    would laser his patients’ eyes with the laser set on the lowest power setting and in
    *
    Honorable John M. Rogers, United States Circuit Judge for the Sixth Circuit, sitting by
    designation.
    1
    Pon was once a licensed doctor but we do not refer to him as one because Florida’s
    Board of Medicine revoked his license in August 2016 as a result of the jury’s guilty verdict.
    2
    Case: 17-11455       Date Filed: 06/29/2020       Page: 3 of 89
    micropulse mode.2 He would then submit a claim to Medicare for the diagnostic
    tests and the laser session. As a result, he would receive from Medicare around
    $1,200 total for each set of diagnostic tests and lasering.
    Pon would bill his micropulse laser sessions under Medicare code 67220, the
    code for “laser photocoagulation for [WMD], for a choroidal neovascular
    membrane,” or in other words, “burning an area of abnormal leaking blood vessels
    with a laser.” Laser photocoagulation is a treatment for WMD that creates a scar
    in the eye by “cooking” shut the abnormal blood vessels (feeder vessels) that are
    characteristic of WMD. But the extremely low power settings that Pon set his laser
    to before each session were not high enough to achieve coagulation, so his
    purported treatments left no scars and did not fit under code 67220. One expert
    testified that Pon’s settings were “way too low” for coagulation purposes, and that
    his method was tantamount to “jump-start[ing] [a car] off a flashlight. It’s so little
    energy.”
    And Pon agreed. He described his purported treatment technique — which
    he referred to as “the micropulse laser technique for treatment of feeder vessels”
    — as treating WMD while leaving “no or minimal scarring.” According to Pon,
    2
    The laser that Pon used has several different user-selectable modes of operation. When
    micropulse mode is selected, the laser is on for only a predetermined percentage of the exposure
    time. For example, a 15 percent duty cycle means that the laser is on for only 15 percent of the
    exposure time and is off for the remaining 85 percent of the exposure time. Pon would set his
    laser to micropulse mode with a 15 percent duty cycle before lasering his patients’ eyes.
    3
    Case: 17-11455      Date Filed: 06/29/2020   Page: 4 of 89
    “the whole concept” behind his purported treatment was to use the laser to heat up
    the WMD feeder vessels “without causing a burn.” His intention was “to get the
    effect from the laser without causing a burn, coagulation.” In fact, according to
    Pon, he would “virtually never get a scar or a burn” if he did his “technique
    properly.” But Pon continued to bill Medicare for his laser “treatments” under
    code 67220 for laser photocoagulation — or laser scarring.
    And Pon became a top Medicare biller of WMD laser scarring treatment,
    billing Medicare for his micropulse laser (which is intended not to create a scar),
    under code 67220 for laser photocoagulation (which is intended to create a scar).
    The percentage of his patients whom he diagnosed with WMD and billed Medicare
    under code 67220 for laser photocoagulation treatment substantially increased over
    the years. Around 2006, drug injections had supplanted laser photocoagulation as
    the typically favored WMD treatment method, so other ophthalmologists’ laser
    treatments and billing amounts for laser photocoagulation went down. Pon’s, by
    contrast, went up dramatically.
    Pon’s practice produced puzzlement and sowed suspicion. Other doctors
    who also treated Pon’s patients were puzzled about his WMD diagnoses and laser
    “treatments.” In the fall of 2008, for example, Virginia-based doctor Robert Vogel
    was treating his longtime patient, D.M., and noticed that the 83-year-old had
    several left-eye maladies, but not WMD. Because D.M. would be in Florida for
    4
    Case: 17-11455     Date Filed: 06/29/2020   Page: 5 of 89
    the winter months, Dr. Vogel told him to check in with an eye doctor after he got
    there. D.M. chose Pon, who diagnosed him with WMD and micropulse lasered his
    eyes. When D.M. returned to Virginia a few months later, Dr. Vogel was
    “shocked” when D.M. told him that Pon had lasered both of his eyes. Dr. Vogel
    examined both eyes, did not see WMD in either of them, and could not understand
    why either one would have been lasered. Nor did Dr. Vogel see a scar in either eye
    that would indicate Pon had used a laser at settings that would have treated WMD
    if D.M. had actually suffered from it. This “unusual” situation prompted Dr. Vogel
    to tell D.M. to find a doctor other than Pon the next time he went to Florida.
    Other experts observed similar anomalies involving Pon’s practice and
    patients. Optometrist Sam Williams referred some of his own patients to Pon, who
    diagnosed every one of them with WMD. Dr. Williams, who has more than forty-
    five years of experience as an optometrist, became concerned when some of those
    patients told him that Pon had lasered their eyes on multiple occasions. As a result,
    Dr. Williams sent them to other ophthalmologists for second opinions about the
    medical necessity of the suspicious laser treatments. “[O]n every occasion” the
    ophthalmologists found that there was no sign Pon had lasered those patients’ eyes
    in a way that would actually treat WMD or that the patients needed any laser
    treatment for any eye disease. Dr. Williams stopped referring his patients to Pon.
    5
    Case: 17-11455       Date Filed: 06/29/2020      Page: 6 of 89
    Ophthalmologist and retinal specialist Elias Mavrofrides discovered much
    the same thing. He examined at least thirty of Pon’s patients and determined that,
    although many reported having undergone repeated laser treatment by Pon for
    WMD, their eyes showed no signs of the disease. Many of Pon’s patients told Dr.
    Mavrofrides that they were not sure why Pon was lasering their eyes, but “were
    told that they would lose vision without treatment.” Dr. Mavrofrides thought that
    Pon’s reported use of lasers on his patients “over and over and over [was]
    extremely atypical or unusual.” In 2008 an optometrist referred to Dr. Mavrofrides
    a patient Pon had diagnosed with WMD and lasered eight months in a row. After
    examining the patient, Dr. Mavrofrides wrote a letter to the optometrist stating that
    he “honestly d[id] not see any necessity for the [laser] treatments [the patient] has
    had.”
    Sometime before the fall of 2011 the government discovered Pon’s scheme.
    It happened when Special Agent Christian Jurs conducted a data analysis to
    determine whether any doctors were billing Medicare under codes associated with
    what he was told were outdated WMD treatment methods, including laser
    photocoagulation.3 That analysis revealed that Pon was a “significant outlier” with
    3
    Special Agent Jurs is a Medicare fraud investigator who became an agent with the
    United States Department of Health and Human Services after having worked as a naval
    intelligence officer and as an agent for the Naval Criminal Investigative Service. He has worked
    with Medicare data on numerous occasions since he became a HHS special agent nearly two
    decades ago.
    6
    Case: 17-11455    Date Filed: 06/29/2020    Page: 7 of 89
    respect to the Medicare claims he submitted under 67220, the billing code for laser
    photocoagulation. In 2010, for example, Pon had submitted claims under that code
    for approximately 93 percent of his Medicare patients, while his ophthalmologist
    peers had submitted claims under that code for an average of only seven-
    hundredths of one percent of their patients. That is a disparity of about 132-to-1.
    The disparity prompted Agent Jurs to run Pon’s name through a complaint
    database, which showed that an unidentified person had lodged a complaint about
    Pon’s WMD treatment. And that, in turn, prompted him to interview
    approximately thirty doctors who had seen patients whom Pon had diagnosed with
    WMD and micropulse lasered. After Agent Jurs conducted some of those
    interviews, the government obtained a warrant to search Pon’s offices.
    In September 2011 federal law enforcement officers executed the search
    warrant and seized Pon’s patient files along with thousands of photographs and
    videos of his patients’ eyes. The next month the Centers for Medicare and
    Medicaid Services sent Pon a letter notifying him that it had suspended his
    Medicare payments based on what it identified as “credible allegations of [health
    care] fraud.” The suspension letter stated that between 2004 and 2011 Pon had
    submitted Medicare claims under codes associated with laser photocoagulation
    treatment and a type of WMD diagnostic test “that were disproportionate to claims
    submitted by other ophthalmologists for these codes,” and “that many of [Pon’s]
    7
    Case: 17-11455    Date Filed: 06/29/2020   Page: 8 of 89
    patients did not have the underlying medical conditions that would support the
    procedures represented by these codes.”
    Sometime after Pon’s Medicare payments were suspended, Agent Jurs
    retained an expert, Dr. Thomas Friberg, to review the photos and videos of the eyes
    of about 500 patients whom Pon had diagnosed with WMD. Dr. Friberg was asked
    to review whether Pon’s patients did, in fact, have WMD. Dr. Friberg had
    obtained his medical degree from the University of Minnesota, completed an
    ophthalmology residency at Stanford University Medical Center, and held
    fellowships at the Harvard Medical School and the Duke University Eye Center.
    He is a professor of ophthalmology and a professor of bioengineering at the
    University of Pittsburgh, has authored or co-authored more than 175 articles in
    peer-reviewed publications, and has, over the course of his four-decade career,
    received more than $7 million in grants to study age-related eye diseases, including
    WMD.
    Dr. Friberg’s review of the more than 10,000 images of the eyes of patients
    whom Pon had diagnosed with WMD and “treated” took him about a year to
    complete. He found what he saw “shocking.” He realized that he “was looking at
    hundreds of images of patients that had nothing wrong with their eye[s].”
    According to Dr. Friberg, maybe “five to ten” –– only one or two percent –– of the
    500 patients whom Pon had diagnosed with WMD actually had any form of
    8
    Case: 17-11455        Date Filed: 06/29/2020        Page: 9 of 89
    macular degeneration. Dr. Friberg concluded that Pon had shown a “reckless
    disregard for his patients.”
    II. PROCEDURAL HISTORY
    In April 2014 a federal grand jury returned a twenty-count indictment
    against Pon. Each count charged him with health care fraud, in violation of 
    18 U.S.C. § 1347.4
     The indictment alleged that he committed health care fraud by
    falsely diagnosing eleven of his patients with WMD and using those false
    diagnoses as a basis for submitting a total of twenty Medicare reimbursement
    claims (a different one described in each count) for performing both additional
    WMD testing that he knew was medically unnecessary and laser sessions that
    could not actually treat the disease even if the patients had been suffering from it,
    which they had not.5 Pon faced a statutory maximum of ten years per count. 
    18 U.S.C. § 1347
    (a). He went to trial.
    4
    Section 1347 makes it a crime to “‘knowingly and willfully’ engage in a scheme (1) ‘to
    defraud any health care benefit program’ or (2) to use false pretenses to obtain money from ‘any
    health care benefit program,’ ‘in connection with the delivery of or payment for health care
    benefits, items, or services.’” United States v. Bergman, 
    852 F.3d 1046
    , 1065 (11th Cir. 2017)
    (quoting 
    18 U.S.C. § 1347
    ).
    5
    To protect their privacy, the indictment does not refer to the patients by name, and we
    will follow that lead by referring to them as the eleven patients, or individually as Patient One,
    Patient Two, and so on.
    9
    Case: 17-11455     Date Filed: 06/29/2020   Page: 10 of 89
    A. The Daubert Hearing
    Before trial Pon notified the government that he intended to offer the expert
    testimony of Giorgio Dorin, a former director of development at the company that
    manufactured the laser Pon used. Dorin’s proposed testimony boiled down to two
    main points. First, he would testify about the general concepts of lasers and their
    application to eye diseases. Second, he would testify about a “newer method” of
    treating WMD that Pon said he had used on his patients: “subthreshold micropulse
    laser photostimulation.” Dorin would opine that the newer method could be used
    to close feeder vessels in a way that, unlike laser photocoagulation, would not
    leave a scar. Dorin chose to use the term “photostimulation” because the term
    “photocoagulation” suggests that the treatment necessarily produces a visible scar.
    The object of Dorin’s testimony would be to show that the low-power laser
    sessions Pon had subjected his patients to could actually treat WMD and could do
    so without leaving a telltale scar.
    The government moved to exclude Dorin’s proposed testimony under
    Daubert v. Merrell Dow Pharmaceuticals, Inc., 
    509 U.S. 579
     (1993), after its
    medical and laser experts advised it that “Dorin’s assertion regarding subthreshold
    micropulsed laser ‘photostimulation’ is not a medically accepted standard of care
    for the treatment of [WMD].” The government stated in its motion “that the term
    now used by the defense, laser ‘photostimulation[,]’ is apparently an attempt to
    10
    Case: 17-11455     Date Filed: 06/29/2020    Page: 11 of 89
    somehow legitimatize the fact that there is no scarification in the retinas of [Pon’s]
    victims.”
    The district court held a three-day Daubert hearing. Dorin was the only
    witness for the defense. The government put on two witnesses — Dr. Friberg and
    David Buzawa, the co-founder of the company that manufactured Pon’s laser. All
    three of the witnesses testified about whether subthreshold micropulse laser
    photostimulation (which left no scar) could treat WMD.
    At the hearing, Dorin testified that the use of subthreshold micropulse laser
    photostimulation to treat WMD was “[t]heoretical[].” He conceded that he was
    unaware of any journal article stating that it is possible to use subthreshold
    micropulse photostimulation with Pon’s laser to treat WMD. But he talked about
    previous research that he said at least supported the idea. He described a study
    showing that subthreshold micropulse laser treatment was effective for diabetic
    macular edema, but that is a different medical condition than WMD. Defense
    counsel then asked Dorin whether he could, as a result of that one study involving
    diabetic macular edema, infer that subthreshold micropulse laser treatment was
    effective for WMD. Dorin responded: “I don’t see why . . . not, but we don’t have
    so many paper[s] published yet. I have not seen the clinical data.”
    Dorin also discussed a paper he authored that a peer-reviewed
    ophthalmology journal published in 2004, when Dr. Friberg was the journal’s
    11
    Case: 17-11455      Date Filed: 06/29/2020   Page: 12 of 89
    editor-in-chief. In the paper Dorin stated that “laser pulses” could treat WMD by
    closing feeder vessels and could do so without causing “retinal burns.” Dorin’s
    paper concluded, however, that “[i]t does take a ‘leap of faith’ to accept that a
    retina with serious disease can be treated with . . . sub-visible-threshold protocols
    and without the use of additional pharmacological agents.”
    At the Daubert hearing, the government called Dr. Friberg. Dr. Friberg
    testified that Dorin’s proposed theory about subthreshold micropulse laser
    photostimulation had not been tested and had “absolutely not” gained general
    acceptance in the scientific community. He also testified that Dorin’s statement
    that subthreshold micropulse laser photostimulation can produce the same
    beneficial effect as laser photocoagulation was “crazy.” When asked whether there
    was even one study showing that the type of laser Pon used has closed a feeder
    vessel without leaving a scar while in micropulse mode, Dr. Friberg responded:
    “No.” He believed that there was “absolutely no acceptance in the
    ophthalmological community for Dorin’s conjecture.”
    The government’s other witness at the Daubert hearing, David Buzawa, held
    nine patents related to laser technology and had nearly forty years of experience
    with lasers. He was also the co-founder of the company that manufactured Pon’s
    laser. Buzawa testified that the power settings that Pon said he set his laser to
    before each laser session were “unusually low for micropulse.” Buzawa also stated
    12
    Case: 17-11455     Date Filed: 06/29/2020    Page: 13 of 89
    that he had “never heard of or read a publication of successful feeder vessel closure
    using micropulse [mode] at [Pon’s] settings or any settings.” He concluded that
    feeder vessel treatment always creates a visible scar, according to “every paper and
    presentation that [he had] heard or read.”
    At the end of the Daubert hearing, defense counsel admitted that his
    proffered witness “Dorin [was] drawing conclusions that have not yet been
    scientifically tested.” The district court ruled that Dorin could testify about the
    general concepts of lasers and their applications. But he could not offer his
    opinion that subthreshold micropulse laser photostimulation could treat WMD by
    closing feeder vessels. The court found that Dorin’s proposed opinion was
    “conjecture” and ruled that it did not satisfy either Federal Rule of Evidence 702 or
    Daubert. Then came the jury trial.
    B. The Trial
    The jury trial began in September of 2015. The government presented
    nineteen witnesses and introduced more than 700 exhibits during its seven-day
    case-in-chief.
    Dr. Friberg was one of the government’s first witnesses. He began with an
    overview of the science behind WMD and how it is diagnosed and treated. He
    explained, for example, that laser photocoagulation, which is billed under
    Medicare code 67220, is a WMD treatment that can be used to “cook” feeder
    13
    Case: 17-11455      Date Filed: 06/29/2020   Page: 14 of 89
    vessels. He testified that laser photocoagulation did not “have much uptake” in the
    medical community because the laser leaves behind a scar that can itself impair
    vision. Dr. Friberg also testified that he was “very certain” that if a doctor uses
    “enough [laser] energy . . . to cook the feeder vessel, you’re going to leave a
    [scar].” And he stated that he was “[a] hundred percent” certain that Pon’s
    micropulse laser technique could not close a feeder vessel.
    Dr. Friberg also explained the science behind drug injections, another WMD
    treatment that was introduced after laser photocoagulation. He testified that “there
    is no [WMD] treatment that we know of that is better than these [drug injections].”
    Dr. Friberg then described how Agent Jurs had retained him to review the
    photos and videos of the eyes of the approximately 500 patients whom Pon had
    diagnosed with WMD and “treated” with his micropulse laser technique. Dr.
    Friberg described how his review of those photos and videos revealed that the vast
    majority of those patients did not actually have WMD. For that reason, what he
    saw in his review “got [him] kind of mad.” According to Dr. Friberg, Pon was
    unnecessarily lasering the eyes of patients for a disease they did not have.
    Dr. Friberg discussed in front of the jury hundreds of images of the eyes of
    the eleven patients identified in the indictment — patients Pon had diagnosed with
    WMD and for whom Pon had billed Medicare under code 67220 for laser
    photocoagulation treatment for that disease. Dr. Friberg testified that based on his
    14
    Case: 17-11455     Date Filed: 06/29/2020    Page: 15 of 89
    review of the images he did not see any indication that any of those eleven patients
    had WMD or any evidence of the scarring that necessarily results from laser
    photocoagulation treatment. See infra pp. 41–56.
    The government also presented the testimony of other doctors who had
    personally examined the eleven patients. With each of those doctors the
    government went patient by patient, eliciting testimony about each patient; the
    doctors explained to the jury the medical records they had created to document
    their examinations of the patients. See 
    id.
     None of those doctors concluded that
    any of the eleven patients had WMD when Pon diagnosed them with it. Some of
    those patients did not even have dry age-related macular degeneration, which
    typically precedes WMD. And several doctors echoed Dr. Friberg’s conclusion;
    they testified that treating WMD by using laser photocoagulation always leaves a
    scar indicating the use of that treatment method — a scar that the doctors testified
    they did not see in the eyes of the eleven patients listed in the indictment, even
    though Pon had billed Medicare under code 67220 for the laser photocoagulation
    treatment of each patient.
    One doctor read from a medical record of his own examination of one of the
    eleven patients. Pon had billed Medicare more than ten times under code 67220
    for the laser photocoagulation of that patient. In his own medical record, the
    doctor stated that both of the patient’s retinas were “completely normal.” He
    15
    Case: 17-11455     Date Filed: 06/29/2020    Page: 16 of 89
    testified that he had seen many of Pon’s patients for a second opinion, and all of
    them “had a history of multiple [billed laser photocoagulation] procedures without
    any visible indication for such procedures or any clinical evidence that such
    procedures had been performed.”
    The jury also heard from some of the eleven patients themselves. One of
    them testified that only after a second doctor confirmed that she did not actually
    have WMD was she relieved of the shock and fear she felt as a result of her
    diagnosis. Another testified that Pon never gave her the option of drug injections
    instead of laser treatments, and she “felt terrible” after another doctor told her that
    she did not have WMD. Despite the fact that Pon had diagnosed both of those
    patients with WMD years before the trial, and they had never received any
    medically recognized treatment for it, each of them testified that they still had the
    requisite vision to (and did) drive a car.
    After the government rested, Pon himself took the stand. He testified that he
    ran so many diagnostic tests (and billed Medicare for them) because he wanted to
    be “as comfortable as possible not to miss a diagnosis.” He claimed that the reason
    the patients did not have a scar in their eyes showing that they had undergone the
    laser photocoagulation treatment he had billed Medicare for was his use of what he
    termed his “miraculous treatment.” As had Dorin at the Daubert hearing, Pon
    testified that his micropulse laser technique could not only treat WMD but could
    16
    Case: 17-11455     Date Filed: 06/29/2020    Page: 17 of 89
    do so without leaving a telltale scar. His technique, Pon explained, was to set his
    laser to the lowest power settings before each session and then adjust those settings
    during the session “until [he] s[aw] the reaction that [he] want[ed] to get.” He said
    that he had attended a presentation “in the early 2000s sometime” that discussed
    this purported treatment, which he described as “the most fantastic news [he had]
    ever heard,” and “a major breakthrough.” He did not, however, have any memory
    of when or where the presentation took place. None.
    After hearing the presentation, Pon was “real enthusiastic” that he could use
    the technique described “to help a lot more patients.” Pon said that he believed the
    technology used to perform the technique described in the presentation was “the
    greatest thing since sliced bread,” so he purchased the necessary equipment. But
    he later testified that “it all happened about the same time,” so he couldn’t “recall
    exactly” whether he bought the new equipment before or after the presentation he
    claimed had inspired him.
    Pon said that once he had the equipment, he began to practice the technique
    he had heard about in the presentation. He first attempted the technique “on the
    patients that [we]re very advanced, so there’s really not very much downside risk
    there.” Eventually he “got the procedure to evolve” so that the risk was “almost
    zero.” He did not say whether he had billed Medicare under code 67220 for laser
    17
    Case: 17-11455     Date Filed: 06/29/2020   Page: 18 of 89
    photocoagulation on these early, experimental patients as he had billed Medicare
    for laser photocoagulation on the patients listed in the indictment.
    Pon testified that an important part of his purported treatment was his ability
    to identify and diagnose WMD in its very early stages. He claimed that by using
    the new technology he could “visualize, directly visualize, these blood vessels”
    that caused WMD. But, even with the new technology, “finding the feeder vessel
    . . . is extremely difficult, even for someone” with a lot of experience diagnosing
    WMD. Pon testified that learning how to accurately interpret the diagnostic
    images and identify the feeder vessel locations “takes a lot of learning,” and “takes
    years, literally years, to learn how to do.”
    Pon admitted he did not “know of anybody specifically” who used the same
    micropulse laser technique to treat WMD. He said that one reason he might be the
    only one doing so is that the technique has “a steep learning curve.” But he was
    “too busy” — despite taking at least two months of vacation each year — and
    didn’t “feel obligated” to publish anything describing his technique or the
    treatment results he was achieving.
    After Pon’s testimony, the defense called thirteen of his patients and the
    spouse of one deceased patient. Only one of those patients was among the eleven
    listed in the twenty counts of the indictment. They generally testified that they
    thought Pon was generous and trustworthy and that their vision had improved after
    18
    Case: 17-11455   Date Filed: 06/29/2020   Page: 19 of 89
    seeing him. They were not, of course, qualified to testify whether they had ever
    actually had WMD.
    After the government presented some rebuttal testimony, Pon presented
    some surrebuttal testimony, and the case eventually went to the jury, which found
    him guilty on all twenty counts.
    C. The Sentencing
    At Pon’s sentence hearing, the district court rejected the probation office’s
    finding and the government’s argument that the amount of loss attributable to
    Pon’s fraud scheme was more than $11 million. Instead, the court found that the
    loss amount was approximately $7 million, which resulted in an 18-level
    enhancement to the base offense level. The court’s application of that and other
    enhancements yielded an advisory guidelines range of 121 months to 151 months
    in prison. The court sentenced Pon to 121 months in prison on each count, to run
    concurrently.
    III. THE CONVICTION ISSUES
    Pon raises two contentions about his convictions, neither of which questions
    the sufficiency of the evidence to convict him. First, he contends that under
    Daubert and Federal Rule of Evidence 702, the district court should have allowed
    his expert to testify about the use of subthreshold micropulse photostimulation as a
    treatment for WMD. Second, Pon contends that the district court should not have
    19
    Case: 17-11455     Date Filed: 06/29/2020    Page: 20 of 89
    allowed the government to present rebuttal evidence showing that he billed
    Medicare for performing services on patient J.L.’s blind left eye. In the alternative,
    he argues that even if that rebuttal evidence was properly admitted, the court
    should have allowed him to present all of his surrebuttal evidence.
    A. The Daubert Issue
    It is not easy to persuade a court of appeals to reverse a district court’s
    judgment on Daubert grounds. United States v. Brown, 
    415 F.3d 1257
    , 1264 (11th
    Cir. 2005). Doing so is tough toil because the “theme that shapes appellate review
    in this area is the limited nature” of that review. 
    Id.
     We review evidentiary
    decisions under the abuse of discretion standard. 
    Id.
     at 1264–65 (citing Gen. Elec.
    Co. v. Joiner, 
    522 U.S. 136
    , 141 (1997)). And under that standard district courts
    have a “significant” range of choice, which is to say that we defer to their
    evidentiary “decisions to a considerable extent.” Id. at 1265; accord McCorvey v.
    Baxter Healthcare Corp., 
    298 F.3d 1253
    , 1257 (11th Cir. 2002) (“[O]ur review of
    evidentiary rulings by trial courts . . . is very limited.”) (quotation marks omitted).
    The deference we show trial courts on evidentiary rulings is especially
    pronounced in the Daubert context, where the abuse of discretion standard places a
    “heavy thumb” — “really a thumb and a finger or two” — “on the district court’s
    side of the scale.” Brown, 
    415 F.3d at 1268
    . That’s done for a number of reasons.
    The district court occupies the best position to rule on Daubert issues given its
    20
    Case: 17-11455     Date Filed: 06/29/2020    Page: 21 of 89
    familiarity “with the procedural and factual details” of the trial, which it presides
    over and is immersed in. 
    Id. at 1266
    . The rules that control the admission of
    expert testimony “must be applied in case-specific evidentiary circumstances that
    often defy generalization.” 
    Id.
     And deference maintains the importance of the trial
    and discourages appeals of rulings about expert witness testimony. See 
    id.
     As a
    result, “the task of evaluating the reliability of expert testimony is uniquely
    entrusted to the district court,” and we must grant “the district court considerable
    leeway in the execution of its duty.” Rink v. Cheminova, Inc., 
    400 F.3d 1286
    ,
    1291 (11th Cir. 2005) (citations and quotation marks omitted). We do so mindful,
    of course, that granting that leeway “is not the same thing as abdicating appellate
    responsibility.” Brown, 
    415 F.3d at 1266
    .
    After holding a three-day Daubert hearing, the district court found that
    Dorin’s theory that subthreshold micropulse photostimulation could treat WMD by
    closing feeder vessels was unreliable. As a result, it allowed Dorin to testify about
    only the general concepts of lasers and their application to eye diseases. That
    ruling was not an abuse of discretion.
    Federal Rule of Evidence 702 “controls the admission of expert testimony.”
    United States v. Frazier, 
    387 F.3d 1244
    , 1259 (11th Cir. 2004) (en banc). Under
    that rule expert witnesses may testify if, among other things, their “testimony is the
    product of reliable principles and methods.” Fed. R. Evid. 702(c). Determining
    21
    Case: 17-11455     Date Filed: 06/29/2020    Page: 22 of 89
    whether expert testimony is the product of “reliable principles and methods” is the
    province of the Daubert test. See City of Tuscaloosa v. Harcros Chems., Inc., 
    158 F.3d 548
    , 562 (11th Cir. 1998) (stating that courts must determine whether “the
    methodology by which the expert reaches his conclusions is sufficiently reliable as
    determined by the sort of inquiry mandated in Daubert”).
    Daubert instructs that a reliability determination involves four main inquiries
    about the expert’s theory or technique: “(1) whether it can be (and has been) tested;
    (2) whether it has been subjected to peer review and publication; (3) what its
    known or potential rate of error is, and whether standards controlling its operation
    exist; and (4) whether it is generally accepted in the field.” Brown, 
    415 F.3d at
    1267 (citing Daubert, 
    509 U.S. at
    593–94).
    In Joiner the Supreme Court added another inquiry to gauge reliability:
    whether there is “an analytical gap between the data and the opinion proffered.”
    
    522 U.S. at 146
    ; accord McDowell v. Brown, 
    392 F.3d 1283
    , 1300 (11th Cir.
    2004) (“[A]n expert opinion is inadmissible when the only connection between the
    conclusion and the existing data is the expert’s own assertions . . . .”) (citing
    Joiner, 
    522 U.S. at 146
    ). If the analytical distance between the data and the
    opinion proffered “is simply too great,” a court may conclude that the opinion is
    unreliable. Joiner, 
    522 U.S. at 146
    .
    22
    Case: 17-11455     Date Filed: 06/29/2020    Page: 23 of 89
    Here, three of the four Daubert factors weigh against the reliability of
    Dorin’s theory. First, Dorin testified that although his theory could be tested, it has
    not been. Dr. Friberg agreed. So did defense counsel, who conceded that “Dorin
    [was] drawing conclusions that have not yet been scientifically tested.” And like
    Pon, Dorin acknowledged that he did not “know of anybody doing it.” Second,
    Pon failed to provide evidence about the theory’s known or potential rate of error
    and whether any standards exist to control for error. Dorin himself acknowledged
    that he “ha[d] not seen . . . clinical data” about it. And third, the record shows that
    Dorin’s theory is not generally accepted in the ophthalmology field. Dr. Friberg
    testified that the theory has “[a]bsolutely not” gained that acceptance. Buzawa’s
    testimony that “[f]eeder vessel treatment has always been superthreshold,” instead
    of subthreshold, according to “every paper and presentation that [he had] heard or
    read” confirmed the point.
    That leaves only one factor that weighs — ever so slightly — in favor of
    reliability: Dorin’s peer-reviewed paper mentioning the theory. But just as
    “[p]ublication . . . is not a sine qua non of admissibility,” Daubert, 
    509 U.S. at 593
    ,
    publication alone is not enough to conclude that a district court abused its
    discretion in not admitting expert testimony, see Allison v. McGhan Med. Corp.,
    
    184 F.3d 1300
    , 1313 (11th Cir. 1999).
    23
    Case: 17-11455      Date Filed: 06/29/2020      Page: 24 of 89
    A further indication that Dorin’s theory was unreliable is the analytical gap
    between it and the research that Dorin said supports it. See Joiner, 
    522 U.S. at 146
    .
    At the hearing, Dorin suggested that because a study showed subthreshold
    micropulse laser treatment can treat diabetic macular edema, his theory that it
    could treat WMD is sound. That is a “leap[] from an accepted scientific premise to
    an unsupported one.” Allison, 
    184 F.3d at 1314
    . Diabetic macular edema is a
    different condition than WMD. Between the premise that subthreshold micropulse
    laser treatment can treat the first condition and Dorin’s theory that it can treat the
    second one, there is an analytical gap.
    Instead of properly bridging that gap, Dorin tried to ipse dixit over it; but a
    bald assertion cannot carry the Daubert burden. See Williams v. Mosaic Fertilizer,
    LLC, 
    889 F.3d 1239
    , 1249 (11th Cir. 2018) (“[N]othing in either Daubert or the
    Federal Rules of Evidence requires a district court to admit opinion evidence that is
    connected to existing data only by the ipse dixit of the expert.”) (quoting Joiner,
    
    522 U.S. at 146
    ). The district court concluded that “there [was] simply too great
    an analytical gap between the data and the opinion proffered.” Joiner, 
    522 U.S. at 146
    . That was not an abuse of discretion but a proper exercise of the “considerable
    leeway” the court had. Kumho Tire Co. v. Carmichael, 
    526 U.S. 137
    , 152 (1999).6
    6
    Pon also argues that the district court violated his Sixth Amendment right to put on a
    meaningful defense because it “mechanistically” applied the Daubert factors. We disagree. The
    24
    Case: 17-11455        Date Filed: 06/29/2020        Page: 25 of 89
    B. The Rebuttal Issue
    Pon also contends that his convictions must be reversed because the district
    court erred in two of the evidentiary rulings it made during his fourteen-day trial:
    (1) allowing the government to present rebuttal evidence showing that he billed
    Medicare for performing certain medical services on J.L., who was one of his
    patients, and (2) partially limiting the scope of his surrebuttal evidence about J.L.
    We review both of those evidentiary rulings only for an abuse of discretion. See
    Frazier, 
    387 F.3d at 1270
    ; United States v. Haimowitz, 
    706 F.2d 1549
    , 1560 (11th
    Cir. 1983). And an abuse of discretion does “not warrant reversal where the
    resulting error was harmless.” United States v. Barton, 
    909 F.3d 1323
    , 1330 (11th
    Cir. 2018).
    One of the fourteen defense witnesses (not counting Pon) was J.L., who took
    the stand on the eleventh day of the trial. Like some of Pon’s other patients who
    appeared as defense witnesses, J.L. testified about his history as Pon’s patient and
    described him as generous and trustworthy. He also told the jury that in 1994 both
    of his retinas had detached because of a complication from diabetes and Pon had
    performed surgery that year on each eye — the left eye in July and the right eye in
    August. Pon knew J.L. was unemployed and uninsured at the time and performed
    district court gave ample reasons why three of those factors weighed against the reliability of
    Dorin’s theory and outweighed the fourth factor.
    25
    Case: 17-11455     Date Filed: 06/29/2020    Page: 26 of 89
    the surgeries without any guarantee he would be paid. The 1994 surgery on J.L.’s
    right eye was successful, but the one on his left eye was not; he lost all of his sight
    in it soon after that surgery.
    Defense counsel also put into evidence excerpts of Pon’s treatment records
    for J.L. Those records included logs in which Pon documented procedures he had
    performed on J.L.’s right eye between 2004 and 2015. They also indicated that
    Pon had diagnosed J.L. with WMD in 2009 and had micropulse lasered J.L’s right
    eye several times. The excerpts from Pon’s records of treating J.L. did not list any
    tests or procedures that Pon had performed on J.L.’s blind left eye.
    During cross-examination, the prosecutor asked J.L. when Pon had last
    performed any procedure on his left eye, the one in which he had been completely
    blind for more than twenty years. J.L. said it had “been a couple years”; he said
    Pon did a “regular eye check on it,” which involved an exam with “the eye charts,”
    an “ultrasound,” and “pictures,” but that Pon had done no “major procedures” on
    his left eye. The prosecutor then asked J.L. whether Pon had ever done “any kind
    of an injection” or any “dye tests” in J.L.’s left eye. J.L. responded: “No. I’ve
    never had anything done in my left eye.” On redirect, J.L. reiterated that Pon had
    not done “any tests on [his] left eye,” including fluorescein angiograms, but Pon
    had examined that eye “a couple times” by looking at it “through a lens” to see if
    he could improve the vision in it. J.L.’s firm testimony that Pon had never done
    26
    Case: 17-11455      Date Filed: 06/29/2020      Page: 27 of 89
    any fluorescein angiograms on his left eye was significant because it contradicted
    the bills Pon submitted to Medicare on at least a half dozen occasions — bills for
    performing fluorescein angiogram tests on J.L.’s totally blind left eye. See infra
    pp. 30–32.
    In light of J.L.’s testimony and the medical records Pon’s attorney had put
    into evidence, the government sought to introduce through one of its agents
    rebuttal evidence in the form of a spreadsheet and related testimony. Agent Jurs
    had created the spreadsheet after J.L.’s testimony by looking through Pon’s
    Medicare claims history for billings related to J.L.’s left eye after 1994, when he
    had lost all of his sight in it. The billing records for the decade between 1994 and
    2004 were not available,7 but the records from 2004 until the trial in 2015 were.
    The spreadsheet showing the billings and Agent Jurs’ testimony established
    that Pon had billed Medicare for performing services on J.L.’s left eye –– in which
    he had been blind since 1994 –– 52 times between 2004 and 2015. Those 52
    billings totaled approximately $19,500 and, aside from three billings for a January
    2009 surgery on the blind eye (which Pon would later testify were merely the
    7
    Agent Jurs testified that he wasn’t certain why he had not been able to access Pon’s
    Medicare billing records before 2004. He thought the most likely explanation was that the
    Medicare system did not give records that “go back, you know, to when the earth cooled. They
    usually go [back] a five- or ten-year time frame.”
    27
    Case: 17-11455     Date Filed: 06/29/2020    Page: 28 of 89
    result of clerical errors), all of the billings were for ophthalmic ultrasounds,
    fluorescein angiograms, and fundus photography, which are diagnostic tests.
    Pon billed Medicare all of those times and for all of that money claiming
    that he had done procedures on J.L.’s blind left eye, including fluorescein
    angiograms, even though his own witness, J.L., testified that Pon never performed
    a fluorescein angiogram or any test involving the injection of dye on his left eye.
    All Pon had ever done on that eye, J.L. insisted, was perform a “regular eye check
    on it,” and examine it by looking through a lens “a couple of times.” His
    testimony evidenced, at the very least, that Pon’s six billings for fluorescein
    angiograms, which involve the injection of dye, on J.L.’s left eye were fraudulent.
    Defense counsel moved to exclude the spreadsheet and Agent Jurs’
    testimony about it, arguing that the evidence was not proper rebuttal. The district
    court allowed the government to present the rebuttal evidence because the court
    recalled (incorrectly, it turned out) that the defense, during J.L.’s testimony, had
    been the first to bring up the fact that Pon had treated J.L.’s blind left eye. Pon
    asserts that ruling was reversible error. It wasn’t.
    Rule 611(a) vests district courts with authority to “exercise reasonable
    control over the mode and order of examining witnesses and presenting evidence.”
    Fed. R. Evid. 611(a). District courts have “broad discretion” in exercising that
    authority and will not be reversed except for abuse of that discretion. United States
    28
    Case: 17-11455     Date Filed: 06/29/2020    Page: 29 of 89
    v. Hill, 
    643 F.3d 807
    , 845 (11th Cir. 2011); accord Haimowitz, 
    706 F.2d at 1560
    .
    Pon presented J.L.’s testimony as an example of how he had treated a patient out of
    the goodness of his heart and not for a profit motive. In light of that, the district
    court did not abuse its discretion in admitting billings Pon had generated for
    services he claimed to have rendered on that patient’s blind eye.
    C. The Surrebuttal Issue
    1. The Procedural Facts
    Pon alternatively asked the district court, if it was not going to keep out the
    government’s rebuttal evidence, to let Pon retake the stand and present as
    surrebuttal evidence his explanation for billing Medicare for services on J.L.’s
    blind left eye. The court reserved a ruling on that alternative request until after the
    government presented its rebuttal evidence.
    After the government did so, Pon renewed his request to present surrebuttal
    testimony, arguing that he had not had an “opportunity to respond” to the
    “impression” the government created that Pon improperly conducted and billed for
    treatments on a blind eye. The district court characterized the government’s
    rebuttal evidence as “very damning” and stated that it had “this idea of fairness
    tug[ging]” at it, but its “inclination” was to deny the defense’s request that Pon be
    allowed to testify again. The court also asked “the further question of whether, in
    deference to . . . Dr. Pon’s Sixth Amendment right . . . he should be given an
    29
    Case: 17-11455       Date Filed: 06/29/2020   Page: 30 of 89
    opportunity to offer an explanation” about the billed procedures for J.L.’s blind left
    eye. The court gave the attorneys the weekend to research the surrebuttal issue and
    indicated it would do the same.
    On Monday, the court heard argument from both sides about whether it had
    erred by allowing the government’s rebuttal testimony and, if so, how any error
    should be remedied. Neither side mentioned the Sixth Amendment or any other
    constitutional right that Pon might have to present surrebuttal testimony. Before
    ruling, the court allowed Pon to proffer the testimony he wished to present in
    response to the government’s rebuttal evidence. He took the stand in a testimonial
    proffer, stating that he had performed services on J.L.’s blind left eye to determine
    whether it had a problem that could lead to complications that might result in a
    complete loss of vision in the right eye.
    Pon testified that ophthalmic ultrasounds, which made up 41 of the 52
    billings in the spreadsheet, are used to look for abnormalities in the eye. And in
    J.L.’s case, “it’s very important to examine his left eye and continue to examine his
    left eye” to make sure he was not developing sympathetic ophthalmia — a
    condition that can lead to blindness in both eyes. For that reason, Pon said that it
    was necessary to examine J.L.’s left eye “periodically.” But Pon didn’t explain
    what “periodically” meant, and he didn’t explain why he needed to examine J.L.’s
    left eye as frequently as he billed Medicare for doing. The records proved that Pon
    30
    Case: 17-11455     Date Filed: 06/29/2020    Page: 31 of 89
    sometimes billed Medicare for performing ophthalmic ultrasounds on J.L.’s left
    eye multiple times in one month and, on at least four occasions, twice on the same
    day.
    When asked about the six fluorescein angiograms he had billed Medicare for
    conducting on J.L.’s blind left eye, Pon said they are “a very useful test to help
    diagnose sympathetic ophthalmia.” Of course, J.L. himself had emphatically
    testified that Pon never performed a fluorescein angiogram on his left eye. Pon
    didn’t offer any explanation for that contradiction.
    Finally, Pon also proffered that the January 2009 surgery was done on J.L.’s
    right eye, not his left as Pon had billed Medicare. He said that billing for surgery
    on the left eye resulted from a “clerical error.”
    After the proffer, defense counsel argued that it would be “incorrect” and
    “misleading” to prevent Pon from testifying about the clerical error in the billing of
    the January 2009 surgery. The district court agreed and decided to let Pon testify
    that he billed for surgery on the wrong eye as a result of a clerical error. The court
    would not allow Pon to testify about any of the numerous non-surgical services on
    the blind left eye and why he claimed they were necessary.
    After the jury returned, Pon took the stand and testified that the billing for
    surgery on J.L’s left eye in 2009 was a clerical error, and that surgery actually had
    been performed on J.L.’s right eye. On cross-examination, Pon admitted that those
    31
    Case: 17-11455         Date Filed: 06/29/2020   Page: 32 of 89
    three 2009 clerical errors about the surgical services were “just three entries out of
    two pages of entries,” and that the total billing for those three entries was “less
    than $3,000.” The two pages of entries showed that Pon had billed $16,441 for the
    49 non-surgical services on J.L.’s blind left eye — billings that Pon never claimed
    were the result of clerical error.
    During closing arguments to the jury, the government spent its time and
    aimed its arguments at the evidence involving the fraudulent billings for treatments
    Pon claimed to have rendered to the eleven patients listed in the indictment —
    evidence it had presented through nineteen witnesses and nearly 760 exhibits over
    seven days of the fourteen-day trial. It mentioned J.L. (who had testified for less
    than one hour of the trial), but just barely. It described him only as someone Pon
    had incorrectly diagnosed with WMD. It said nothing at all about any services that
    Pon had billed for J.L.’s blind left eye. Not one word.
    Defense counsel, by contrast, discussed J.L. at length in his closing
    argument. Referring to the surgery Pon had performed on J.L. in 1994, for which
    Pon did not know if he would get paid, counsel asked the jury: “Is that, ladies and
    gentlemen, what a fraudster would do?” And addressing the rebuttal evidence that
    Pon billed for services on J.L.’s blind left eye, counsel argued:
    I submit to you that the diagnostic tests and examinations that Dr. Pon
    did, whether it’s on the right eye, which still was viable, or the left eye,
    which he was legally blind in, are still tests that are appropriate for a
    32
    Case: 17-11455     Date Filed: 06/29/2020     Page: 33 of 89
    doctor to do, and there’s absolutely nothing wrong with doing those
    tests and billing Medicare for it.
    However, he did not offer the jury any explanation for why J.L., the witness he
    called who would have been the subject of those tests — including tests involving
    dye injections — would testify under oath that at least some of them had never
    been performed.
    After closing arguments, the court instructed the jury, among other things,
    that Pon was “on trial only for the specific crimes charged in the indictment,” and
    the jury’s task was to determine whether Pon was “guilty or not guilty of those
    specific crimes.” The jury found him guilty of all twenty counts of health care
    fraud, none of which mentioned J.L.
    We review rulings about whether to allow surrebuttal evidence only for an
    abuse of discretion. See Frazier, 
    387 F.3d at 1270
    ; Haimowitz, 
    706 F.2d at 1560
    .
    The district court’s ruling partially granted and partially denied Pon’s request to
    present surrebuttal evidence. The court granted his request to re-take the stand and
    testify that the three billings for surgery on J.L.’s left eye were clerical errors, and
    he had actually performed the surgery on J.L’s functioning right eye. But the court
    denied Pon’s request to testify that the reason he billed for so many diagnostic tests
    on J.L.’s blind left eye was to determine if there was a problem with it that could
    lead to complications that might result in a loss of vision in the right eye.
    33
    Case: 17-11455      Date Filed: 06/29/2020     Page: 34 of 89
    2. The Preservation Issue
    Pon contends the court’s refusal to let him testify to that was both trial error
    and constitutional error. The constitutional error he claims is a violation of his
    Sixth Amendment right “to defend against the government’s evidence” and denial
    of a fair opportunity to respond to the government’s rebuttal testimony. Pon
    clearly preserved the trial error issue in the district court, but it is far from clear
    that he preserved the constitutional issue.
    “No procedural principle is more familiar . . . than that a constitutional right
    may be forfeited in criminal as well as civil cases by the failure to make timely
    assertion of the right before a tribunal having jurisdiction to determine it.” Yakus
    v. United States, 
    321 U.S. 414
    , 444 (1944). To preserve an error in a criminal trial,
    a party must “inform[] the court — when the court ruling or order is made or
    sought — of the action the party wishes the court to take, or the party’s objection
    to the court’s action and the grounds for that objection.” Fed. R. Crim. P. 51(b).
    Failing to contemporaneously object “ordinarily precludes the raising on appeal of
    the unpreserved claim of trial error.” Puckett v. United States, 
    556 U.S. 129
    , 135
    (2009).
    Although a contemporaneous objection preserves an issue for appellate
    review, “not every objection is a constitutional objection.” United States v.
    Candelario, 
    240 F.3d 1300
    , 1304 (11th Cir. 2001). We have held over and over
    34
    Case: 17-11455      Date Filed: 06/29/2020     Page: 35 of 89
    again that to preserve an issue, a litigant must “first clearly present it to the district
    court, that is, in such a way as to afford the district court an opportunity to
    recognize and rule on it.” See, e.g., Juris v. Inamed Corp., 
    685 F.3d 1294
    , 1325
    (11th Cir. 2012) (quotation marks omitted).
    While Pon did preserve through objection and argument the issue of whether
    the district court’s partial limitation on his surrebuttal evidence violated the rules
    governing the presentation of rebuttal and surrebuttal evidence, he never once
    mentioned the Sixth Amendment or argued to the district court that the limitation
    violated that or any other constitutional provision. Our precedent indicates that an
    objection on nonconstitutional grounds is not enough to preserve a constitutional
    issue. For example, in United States v. Chau, 
    426 F.3d 1318
     (11th Cir. 2005), we
    held that the defendant’s hearsay objection in the district court did not preserve the
    Confrontation Clause issue he pressed on appeal. 
    Id.
     at 1321–22 (“[A] hearsay
    objection does not preserve the [Confrontation Clause] issue . . . .”). In United
    States v. Hawkins, 
    934 F.3d 1251
    , 1264 (11th Cir. 2019), we concluded that the
    “tepid objections made by defense counsel” and the “rumblings of concern about
    the phrasing of questions” did not preserve the argument the defendants made on
    appeal that the trial court had admitted improper opinion testimony. And in United
    States v. Elbeblawy, 
    899 F.3d 925
    , 938 (11th Cir. 2018), we held that a defendant
    had not preserved an argument when he only “mentioned it, in passing, in a post-
    35
    Case: 17-11455     Date Filed: 06/29/2020    Page: 36 of 89
    trial reply motion” because the “post-trial remark was neither timely nor
    sufficiently developed” to preserve the issue. Pon did not even mention in passing
    to the district court the constitutional issue he wants to pursue before us.
    It is true that at one point the district court — not Pon — stated: “[T]here’s
    the further question of whether, in deference to . . . Dr. Pon’s Sixth Amendment
    right . . . he should be given an opportunity to offer an explanation at that point.”
    That probably is not enough to preserve the Sixth Amendment issue for appeal,
    even under the view of the treatise that the dissent relies on to reach the contrary
    conclusion. See Dissent at 8 n.4.
    The relevant part of that treatise states:
    [I]f the record reveals that the parties and the court were aware of the
    claim or issue and litigated it, then whether or not it served as the
    basis for determination the claim or issue was raised and is reviewable
    on appeal. Moreover, if the district court sua sponte raised an issue of
    law and explicitly resolved the issue on the merits, that ruling is fully
    reviewable on appeal even though no party raised it below.
    19 James Wm. Moore et al., Moore’s Federal Practice § 205.05(1) (3d ed. 2019)
    (emphases added) (footnotes omitted). Like our precedent, the treatise states that
    the mere mention of an issue does not preserve it. Instead, the issue must have
    been “decide[d],” “litigated,” and “explicitly resolved . . . on the merits” to be
    preserved. Id.
    As our discussion of the surrebuttal argument in the district court has shown,
    the Sixth Amendment issue was not decided, litigated, or explicitly resolved on the
    36
    Case: 17-11455        Date Filed: 06/29/2020       Page: 37 of 89
    merits there. Defense counsel did not even mention it; the government did not
    mention it; and the district court mentioned it only in passing in a single sentence.
    Even after the district court referred to it, defense counsel did not argue that Pon
    had a Sixth Amendment right to present surrebuttal evidence in these
    circumstances. The failure to do so is all the more significant because counsel
    objected on Sixth Amendment grounds to five other rulings against Pon on
    evidentiary issues during the trial.8 But he did not assert or even mention the Sixth
    Amendment in connection with the partial limitation on surrebuttal evidence. On
    this record, the author of the treatise might well say that the Sixth Amendment
    issue does not “fairly appear[] in the record as having been raised or decided.”
    Moore’s § 205.05(1).
    But we don’t have to decide if that Sixth Amendment issue was presented to
    the district court. We can assume that it was. We can make that assumption
    because even if partially limiting Pon’s surrebuttal did violate his Sixth
    8
    For example, in objecting to the district court’s ruling that he could not admit exhibits
    during cross-examination, counsel argued that “the restriction impinge[d] Dr. Pon’s Sixth
    Amendment constitutional right to cross-examination”; he moved for a mistrial after information
    came out about what a nontestifying doctor said, invoking the Sixth Amendment and arguing
    that Pon was “deprived of [his] right to confrontation”; in offering an exhibit that the government
    sought to have excluded, he argued that Pon’s “Sixth Amendment constitutional right to present
    evidence” entitled him to have the exhibit accepted; he sought the court’s permission for Pon to
    confer with counsel during breaks in his testimony, arguing that Pon was entitled to do so
    because of “the right to counsel under the Sixth Amendment”; and he again argued that one of
    Pon’s exhibits should have been admitted because the district court’s “exclusion of [the proffered
    exhibit was] a denial of Dr. Pon’s Sixth Amendment right to present evidence.”
    37
    Case: 17-11455     Date Filed: 06/29/2020    Page: 38 of 89
    Amendment rights, that error was harmless beyond a reasonable doubt, which
    necessarily means that any nonconstitutional error from that limitation was
    harmless as well.
    3. The Harmless Error Standard
    We review preserved assertions of error — both constitutional and
    nonconstitutional error — for harmlessness. See Fed. R. Crim. P. 52(a) (“Any
    error, defect, irregularity, or variance that does not affect substantial rights must be
    disregarded.”); United States v. Olano, 
    507 U.S. 725
    , 734 (1993) (“When the
    defendant has made a timely objection to an error and Rule 52(a) applies, a court
    of appeals normally engages in a specific analysis of the district court record — a
    so-called ‘harmless error’ inquiry — to determine whether the error was
    prejudicial.”).
    As this Court sitting en banc has recognized, the Supreme Court has
    repeatedly held that “the vast majority of constitutional errors that occur at a
    criminal trial, including Sixth Amendment violations, should be examined for
    prejudicial effect and those errors do not require reversal if they are harmless.”
    United States v. Roy, 
    855 F.3d 1133
    , 1167 (11th Cir. 2017) (en banc). The
    harmless error doctrine is important because it “promotes public respect for the
    criminal process by focusing on the underlying fairness of the trial.” Neder v.
    United States, 
    527 U.S. 1
    , 18 (1999) (quotation marks omitted). Review for
    38
    Case: 17-11455      Date Filed: 06/29/2020     Page: 39 of 89
    harmlessness “is also essential to avoid a ‘sporting theory of justice’ and a regime
    of gotcha review.” Roy, 855 F.3d at 1142 (quoting United States v. Agurs, 
    427 U.S. 97
    , 108 (1976)).
    A constitutional error is harmless if the government proves “beyond a
    reasonable doubt that the error complained of did not contribute to the verdict
    obtained.” Chapman v. California, 
    386 U.S. 18
    , 22 (1967). And “[t]o say that an
    error did not contribute to the verdict is . . . to find that error unimportant in
    relation to everything else the jury considered on the issue in question, as revealed
    in the record.” Yates v. Evatt, 
    500 U.S. 391
    , 403 (1991); accord Cape v. Francis,
    
    741 F.2d 1287
    , 1294–95 (11th Cir. 1984) (“If, upon its reading of the trial record,
    the appellate court is firmly convinced that the evidence of guilt was so
    overwhelming that the trier of fact would have reached the same result without the
    tainted evidence, then there is insufficient prejudice to mandate the invalidation of
    the conviction.”).
    A nonconstitutional error, on the other hand, is harmless unless it “resulted
    ‘in actual prejudice because it had substantial and injurious effect or influence in
    determining the jury’s verdict.’” United States v. Guzman, 
    167 F.3d 1350
    , 1353
    (11th Cir. 1999) (quoting United States v. Lane, 
    474 U.S. 438
    , 449 (1986)). If a
    reviewing court “can say with fair assurance . . . that the judgment was not
    substantially swayed by the [nonconstitutional] error,” the court must affirm even
    39
    Case: 17-11455     Date Filed: 06/29/2020    Page: 40 of 89
    if the district court erred. United States v. Hornaday, 
    392 F.3d 1306
    , 1315–16
    (11th Cir. 2004).
    Under both harmless error standards, the reviewing court examines the trial
    record in its entirety to make its prejudice determination. See Neder, 
    527 U.S. at 19
     (constitutional standard); United States v. Sweat, 
    555 F.3d 1364
    , 1367 (11th
    Cir. 2009) (nonconstitutional standard). The government bears the burden of
    showing harmlessness in both situations when the issue was properly preserved by
    timely objection. See, e.g., United States v. Vonn, 
    535 U.S. 55
    , 62 (2002) (noting
    that it is the government’s “burden of showing that any error was harmless” under
    harmless-error review). As may be apparent, the constitutional harmless error
    hurdle is the higher of the two for the government to clear. See generally United
    States v. Mathenia, 
    409 F.3d 1289
    , 1291 (11th Cir. 2005) (noting “the less
    demanding [harmless error] test that is applicable to non-constitutional errors”);
    United States v. Robles, 
    408 F.3d 1324
    , 1327 (11th Cir. 2005) (noting that “[w]hen
    the error is of the constitutional variety, a higher standard is applied” than when the
    error is nonconstitutional). For that reason, a holding that a constitutional error is
    harmless necessarily means that it is also harmless if it happens to be
    nonconstitutional error.
    40
    Case: 17-11455      Date Filed: 06/29/2020   Page: 41 of 89
    4. The Harmlessness of the Assumed Error
    We are persuaded that, even if the district court erred in partially limiting
    Pon’s surrebuttal evidence, and that error violated the Sixth Amendment, it was
    harmless beyond a reasonable doubt. See United States v. Willner, 
    795 F.3d 1297
    ,
    1322 (11th Cir. 2015) (“One circumstance in which courts find constitutional
    errors harmless beyond a reasonable doubt is when the evidence of the defendant’s
    guilt is ‘so overwhelming.’”) (quoting Harrington v. California, 
    395 U.S. 250
    , 254
    (1969)). Here’s why.
    a. The Eleven Patients Listed in the Indictment
    First, the government presented a slew of compelling evidence that not a
    single patient out of the eleven identified in the indictment had WMD, yet Pon had
    diagnosed every one of them with that degenerative eye disease anyway. And
    those patients’ eyes showed no signs at all of having undergone laser
    photocoagulation treatment for WMD, though Pon had billed Medicare under code
    67220 for laser photocoagulation treatment for each patient. The government
    presented the testimony of not one, but a dozen doctors about the patients listed in
    the indictment. Dr. Friberg and eleven other doctors who had examined the eleven
    patients identified in the indictment testified against Pon. All told, the twelve of
    41
    Case: 17-11455       Date Filed: 06/29/2020      Page: 42 of 89
    them collectively had more than 330 years of experience.9 None of those doctors
    could find any evidence that any of the eleven patients identified in the indictment
    had WMD when Pon diagnosed them with it, and they all concluded that the
    patients did not have the telltale scars associated with the laser photocoagulation
    treatment that Pon had billed Medicare for performing on each patient. Because
    the overwhelming amount of the evidence is important, we recount in detail the
    doctors’ testimony about each of the eleven patients.
    (1) Patient One
    About Patient One, the jury heard testimony from three ophthalmologists:
    Dr. Friberg and two others. Dr. Friberg testified that before trial he reviewed
    images of both of Patient One’s eyes, each of which Pon had diagnosed with
    WMD and for each of which he had billed Medicare under code 67220 as though
    he had performed laser photocoagulation treatment. The images of the patient’s
    left eye (the basis for Count One) were taken both on and after the “treatment”
    date, and the images of the patient’s right eye (the basis for Count Two) were taken
    before, on, and after the “treatment” date. Dr. Friberg told the jury about his
    review of those images and explained that he did not see any indication at all that
    9
    Dr. Friberg: 32 years; Dr. Williams: 45 years; Dr. Berger: 31 years; Dr. Magruder:
    26 years; Dr. Gills: 47 years; Dr. Pennachio: 30 years; Dr. Wehrly: 21 years; Dr. Mavrofrides:
    11 years; Dr. Schwenk: 31 years; Dr. Beneke: 24 years; Dr. Vogel: 21 years; Dr. Kraut: 19 years.
    42
    Case: 17-11455     Date Filed: 06/29/2020     Page: 43 of 89
    the patient had WMD in either of her eyes or a scar showing she had actually
    received laser photocoagulation treatment in either eye.
    The second ophthalmologist testified about five examinations he had
    conducted on Patient One after Pon’s diagnosis and purported treatment. He was
    “confident that [the patient] was not” suffering from WMD when he examined her,
    and he said she did not have the disease when Pon billed Medicare for laser
    photocoagulation treatment on her eyes.
    Patient One went to the third testifying ophthalmologist to get a second
    opinion about whether she had WMD. That ophthalmologist had examined Patient
    One on three separate occasions after Pon’s diagnosis and purported laser
    treatment of her eyes. He discussed with the jury the medical records of his
    examinations of Patient One. Based on those three examinations, he testified that
    she did not have WMD when Pon billed Medicare for laser photocoagulation
    treatment of her eyes nor did she have a laser-related scar in her eyes afterwards.
    None of Pon’s excluded surrebuttal evidence, which is the assumed error we are
    talking about, had anything to do with Patient One.
    (2) Patient Two
    About Patient Two, the jury heard from Dr. Friberg and two other
    ophthalmologists. Before trial, Dr. Friberg reviewed images of this patient’s left
    eye, which Pon had diagnosed with WMD and for which he had billed Medicare
    43
    Case: 17-11455     Date Filed: 06/29/2020   Page: 44 of 89
    under code 67220 as though he had performed laser photocoagulation treatment on
    two separate occasions. The images Dr. Friberg reviewed were taken before, on,
    and after the first “treatment” date (the basis for Count Three), and before and on
    the second “treatment” date (the basis for Count Four). Dr. Friberg testified that
    based on his review there was “a high degree of medical certainty” that the patient
    had not had WMD. He also testified that he did not see any indication that the
    patient had a scar in her eye showing she had actually undergone laser
    photocoagulation treatment.
    The second ophthalmologist testified about six examinations he had
    conducted on Patient Two’s eye after Pon’s diagnosis and supposed treatment.
    After reviewing for the jury the medical records of his examinations, he testified
    that this patient did not have WMD when Pon billed Medicare for laser
    photocoagulation treatment of her eye.
    The third ophthalmologist testified that he had examined Patient Two on two
    separate occasions just months before Pon diagnosed her with WMD. He had not
    seen any evidence that the patient had WMD, and he testified that the chance of
    her developing the disease in the brief period between the time he examined her
    and the time Pon billed Medicare for laser photocoagulation of her eye was “very
    unlikely.” None of Pon’s excluded surrebuttal evidence, which is the assumed
    error we are talking about, had anything to do with Patient Two.
    44
    Case: 17-11455     Date Filed: 06/29/2020    Page: 45 of 89
    (3) Patient Three
    Patient Three was also the subject of testimony from Dr. Friberg and two
    other ophthalmologists. Before trial, Dr. Friberg reviewed images of both of this
    patient’s eyes, each of which Pon had diagnosed with WMD and for each of which
    he had billed Medicare under code 67220 as though he had performed laser
    photocoagulation treatment. The images of the patient’s left eye (the basis for
    Count Five) were taken on and after the “treatment” date, and the images of the
    patient’s right eye (the basis for Count Six) were taken before, on, and after that
    date. Dr. Friberg testified that based on his review he did not see any indication
    that on any of those dates the patient had WMD or a scar indicating he had actually
    undergone laser photocoagulation treatment.
    The second ophthalmologist explained to the jury the medical records
    documenting some of Patient Three’s visits with him. He testified to his “shock[]”
    of learning that the patient had purportedly undergone laser photocoagulation
    treatment at Pon’s office just months after he himself had concluded that the
    patient did not have WMD. He also stated that he had examined the patient after
    Pon did and had concluded that the patient did not have WMD or any laser
    photocoagulation scars in his eyes.
    The third ophthalmologist testified that he examined this patient on three
    separate occasions more than four years after Pon’s diagnosis and purported
    45
    Case: 17-11455     Date Filed: 06/29/2020    Page: 46 of 89
    treatment and, on each occasion, he saw no indication that the patient had WMD.
    He also testified that he did not see any laser photocoagulation scars in the
    patient’s eyes. None of Pon’s excluded surrebuttal evidence, which is the assumed
    error we are talking about, had anything to do with Patient Three.
    (4) Patient Four
    The jury heard from Dr. Friberg and another ophthalmologist about Patient
    Four. Before trial, Dr. Friberg reviewed images of this patient’s right eye, which
    Pon had diagnosed with WMD and for which he had billed Medicare under code
    67220 as though he had performed laser photocoagulation treatment on two
    separate occasions. The images Dr. Friberg reviewed were taken before, on, and
    after the two “treatment” dates (the basis for Counts Seven and Eight). Dr. Friberg
    testified that based on his review he did not see any indication that the patient had
    WMD or a scar in her eyes showing that she had actually received laser
    photocoagulation treatment for that disease. Instead, the patient’s eye that Pon said
    suffered from WMD “look[ed] pristine” and there was “[n]o medical reason” to
    laser it.
    The other ophthalmologist testified about his examination of Patient Four
    several years after Pon had diagnosed her with WMD and supposedly treated her.
    He stated that she did not have WMD when Pon diagnosed her with it and billed
    Medicare for laser photocoagulation of it, that he did not see any scarring in her
    46
    Case: 17-11455     Date Filed: 06/29/2020   Page: 47 of 89
    right eye that would indicate she had undergone that treatment, and that she still
    did not have WMD at the time he had examined her eyes. He added that the
    patient’s eyesight was “[v]ery good” for her age. None of Pon’s excluded
    surrebuttal evidence, which is the assumed error we are talking about, had anything
    to do with Patient Four.
    (5) Patient Five
    The jury heard from Dr. Friberg and another ophthalmologist about Patient
    Five. Before trial, Dr. Friberg reviewed images of the patient’s right eye, which
    Pon had diagnosed with WMD and for which he had billed Medicare under code
    67220 as though he had performed laser photocoagulation treatment. The images
    Dr. Friberg reviewed were taken on and after the purported treatment date (the
    basis for Count Nine). Dr. Friberg testified that he was “[v]ery certain” the patient
    did not have WMD. He added that her blood vessels looked “[e]xcellent.” And
    although Pon had billed Medicare for laser photocoagulation of this patient’s right
    eye six times, Dr. Friberg saw no scars indicating she had ever received any laser
    photocoagulation in that eye.
    The second ophthalmologist testified about seven examinations he
    conducted on Patient Five after her optometrist referred her to him for a macular
    degeneration evaluation. All seven of the examinations were after Pon had
    diagnosed Patient Five with WMD and purportedly treated her. Based on his
    47
    Case: 17-11455   Date Filed: 06/29/2020    Page: 48 of 89
    examinations, this ophthalmologist testified that there was no way that Patient Five
    had WMD when Pon diagnosed her with the disease. And he testified that he saw
    no scarring in her right eye that would indicate she had received laser
    photocoagulation treatment for WMD. None of Pon’s excluded surrebuttal
    evidence, which is the assumed error we are talking about, had anything to do with
    Patient Five.
    (6) Patient Six
    The jury heard about Patient Six from Dr. Friberg and two other
    ophthalmologists. Before trial, Dr. Friberg reviewed images of both of the
    patient’s eyes, each of which Pon had diagnosed with WMD and for which he had
    billed Medicare under code 67220 as though he had performed laser
    photocoagulation treatment. The images Dr. Friberg reviewed were taken before
    and after the “treatment” date for this patient’s right eye (the basis for Count Ten)
    and before, on, and after the “treatment” date for this patient’s left eye (the basis
    for Count Eleven). Dr. Friberg testified that based on his review the patient had
    not had WMD in either eye. And he testified that the patient’s eyes had no scars
    indicating that she had ever received any laser photocoagulation treatment.
    The second ophthalmologist testified about his treatment of Patient Six over
    a nine-year period that overlapped with the time Pon had treated her. This
    48
    Case: 17-11455     Date Filed: 06/29/2020    Page: 49 of 89
    ophthalmologist reviewed for the jury his medical records from twelve
    examinations of the patient and testified that she had never showed signs of WMD.
    The third ophthalmologist testified about examinations he had conducted on
    Patient Six after Pon’s diagnosis and purported treatment. He stated that she did
    not have WMD and did not have any scarring from laser photocoagulation
    treatments. None of Pon’s excluded surrebuttal evidence, which is the assumed
    error we are talking about, had anything to do with Patient Six.
    (7) Patient Seven
    The jury heard from Dr. Friberg and two other ophthalmologists about
    Patient Seven. Before trial, Dr. Friberg reviewed images of both of the patient’s
    eyes, each of which Pon had diagnosed with WMD and for each of which he had
    billed Medicare under code 67220 as though he had performed laser
    photocoagulation treatment. The images Dr. Friberg reviewed were taken before,
    on, and after the “treatment” date for this patient’s left eye (the basis for Count
    Twelve) and on the “treatment” date for this patient’s right eye (the basis for Count
    Thirteen). Dr. Friberg testified that based on his review the patient never had
    WMD in either eye and did not have a laser scar indicating that he ever received
    laser photocoagulation treatment in either eye.
    The second ophthalmologist examined Patient Seven after Pon had billed
    Medicare numerous times for laser photocoagulation treatment of his right eye.
    49
    Case: 17-11455     Date Filed: 06/29/2020    Page: 50 of 89
    This ophthalmologist testified that he found “no evidence whatsoever of any
    previous laser treatment.” He was “[a] hundred percent” certain that the patient
    did not have WMD or any scars indicating laser treatment.
    The third ophthalmologist examined Patient Seven after the patient was
    referred to him for a cataract evaluation. He went over for the jury the five
    examinations he had conducted on Patient Seven after Pon’s diagnosis and
    purported treatment. None of the evaluations showed any sign of WMD. None of
    Pon’s excluded surrebuttal evidence, which is the assumed error we are talking
    about, had anything to do with Patient Seven.
    (8) Patient Eight
    The jury heard about Patient Eight from Dr. Friberg, two other
    ophthalmologists, and an optometrist with 45 years of experience. Before trial, Dr.
    Friberg reviewed images of both of the patient’s eyes, each of which Pon had
    diagnosed with WMD and for each of which he had billed Medicare under code
    67220 as though he had performed laser photocoagulation treatment. Those
    images were taken before, on, and after the “treatment” date for this patient’s left
    eye (the basis for Count Fourteen) and before and on the “treatment” date for this
    patient’s right eye (the basis for Count Fifteen). Dr. Friberg testified that based on
    his review the patient did not have WMD in his left eye and did not have a scar
    indicating he had ever received laser photocoagulation treatment in either eye. Dr.
    50
    Case: 17-11455     Date Filed: 06/29/2020   Page: 51 of 89
    Friberg also testified that there was no WMD in the area of the patient’s right eye
    that Pon had marked for treatment. That area, Dr. Friberg added, was “quite
    pristine.”
    The second ophthalmologist testified about five examinations conducted on
    Patient Eight — one before and four after Pon’s diagnosis and purported laser
    photocoagulation treatment of the patient’s eyes. He testified that none of the
    examinations showed any indication of WMD or scarring from laser
    photocoagulation treatment.
    The third ophthalmologist performed cataract surgery on Patient Eight after
    Pon had diagnosed the patient with WMD and billed Medicare for laser
    photocoagulation treatment of both eyes. This ophthalmologist discussed his pre-
    and post-operation examinations of the patient’s eyes and testified that he never
    saw any evidence of WMD.
    The optometrist was another witness who testified about his examinations of
    Patient Eight’s eyes after Pon had diagnosed them with WMD and purportedly
    treated them. He testified that he saw no evidence of the scarring that would
    accompany laser photocoagulation treatment, and no evidence of WMD in the
    patient’s eyes. And he explained that because the patient did not have WMD when
    he examined him after Pon had diagnosed and supposedly treated his eyes, there
    was no way the patient had WMD when Pon diagnosed him with it. None of Pon’s
    51
    Case: 17-11455     Date Filed: 06/29/2020   Page: 52 of 89
    excluded surrebuttal evidence, which is the assumed error we are talking about,
    had anything to do with Patient Eight.
    (9) Patient Nine
    The jury heard from Dr. Friberg and another ophthalmologist about Patient
    Nine. Before trial, Dr. Friberg reviewed images of both of this patient’s eyes, each
    of which Pon had diagnosed with WMD and for each of which he had billed
    Medicare under code 67220 as though he had performed laser photocoagulation
    treatment. The images Dr. Friberg reviewed were taken on and after the
    “treatment” date for this patient’s left eye (the basis for Count Sixteen) and before,
    on, and after the “treatment” date for this patient’s right eye (the basis for Count
    Seventeen). Dr. Friberg testified that based on his review the patient did not have
    WMD in either eye at the time Pon diagnosed her with that disease, and she did not
    have scarring from laser photocoagulation treatment in either eye.
    The other ophthalmologist examined Patient Nine after Pon had diagnosed
    her with WMD and purportedly treated her eyes. This ophthalmologist testified
    that he was “[a] hundred percent” certain that she had not had WMD or any
    scarring from laser photocoagulation treatment for that disease. None of Pon’s
    excluded surrebuttal evidence, which is the assumed error we are talking about,
    had anything to do with Patient Nine.
    52
    Case: 17-11455     Date Filed: 06/29/2020   Page: 53 of 89
    (10) Patient Ten
    The jury heard about Patient Ten from Dr. Friberg, from another
    ophthalmologist, and also from an optometrist with 45 years of experience. Before
    trial, Dr. Friberg reviewed images of the patient’s left eye, which Pon had
    diagnosed with WMD and for which he had billed Medicare under code 67220 as
    though he had performed laser photocoagulation treatment. The images Dr.
    Friberg reviewed were taken on the “treatment” date for this patient’s left eye (the
    basis for Count Eighteen). He testified that based on his review the patient did not
    have WMD at the time Pon diagnosed her with that disease, nor did she have a scar
    indicating that she had ever received laser photocoagulation treatment for the
    disease.
    The other ophthalmologist testified about his treatment of Patient Ten after
    Pon had diagnosed her with WMD and purportedly treated her. Patient Ten had
    come to him for a second opinion about whether she had macular degeneration.
    He testified that he was “[a] hundred percent certain” that she did not have WMD
    or any scars from laser treatment for that disease.
    The optometrist told the jury about four examinations he had conducted on
    Patient Ten after Pon’s diagnosis and purported laser treatment. He testified that
    he never saw any indication that she had WMD and he had never seen any scarring
    from laser photocoagulation treatment for that disease. None of Pon’s excluded
    53
    Case: 17-11455     Date Filed: 06/29/2020   Page: 54 of 89
    surrebuttal evidence, which is the assumed error we are talking about, had anything
    to do with Patient Ten.
    (11) Patient Eleven
    The jury heard about Patient Eleven from Dr. Friberg, from another
    ophthalmologist, and from the optometrist with 45 years of experience. Before
    trial, Dr. Friberg reviewed images of this patient’s right eye that Pon had diagnosed
    with WMD and for which he had billed Medicare under code 67220 as though he
    had performed laser photocoagulation treatment on two separate occasions. The
    images he reviewed were taken before, on, and after the first “treatment” date (the
    basis for Count Nineteen) and on and after the second “treatment” date (the basis
    for Count Twenty). Dr. Friberg testified that based on his review, he was
    “[c]ertain” that the patient did not have WMD when Pon diagnosed her with that
    disease, and that she did not have a scar indicating she had received laser
    photocoagulation treatment for the disease.
    The other ophthalmologist told the jury that Patient Eleven had been referred
    to him for a second opinion about whether Pon’s frequent lasering of her eye was
    necessary. He testified that he examined the patient twice and both examinations
    showed no evidence of WMD and no scar indicating she had received laser
    photocoagulation treatment for that disease.
    54
    Case: 17-11455     Date Filed: 06/29/2020    Page: 55 of 89
    The optometrist testified about his treatment of Patient Eleven over a period
    of six years, some of which overlapped with Pon’s treatment of her. He testified
    that none of his examinations revealed any sign of WMD. None of Pon’s excluded
    surrebuttal evidence, which is the assumed error we are talking about, had anything
    to do with Patient Eleven.
    (12) Summary
    In regard to the eleven patients whose cases were the basis for all of the
    counts in the indictment, the jury heard from twelve different doctors, each of
    whom testified that Pon had diagnosed patients with WMD when those patients
    clearly had never had it. Those doctors also testified that none of those patients
    had the telltale scarring that necessarily results from the laser photocoagulation
    treatment that Pon billed Medicare for performing on them. Other than himself,
    Pon presented no ophthalmologist or optometrist to testify that any one of the
    eleven patients actually had WMD at the time he purportedly treated them for it or
    had the scarring that would necessarily have resulted from the laser
    photocoagulation treatment he billed Medicare for performing. Not only that, but
    he billed Medicare for laser photocoagulation treatment of the eleven patients,
    which necessarily causes a scar, even though Pon himself conceded that his
    treatment did not cause any scarring. And nobody (other than Pon) testified to
    support his claim that WMD could be laser-treated without scarring. None of
    55
    Case: 17-11455     Date Filed: 06/29/2020   Page: 56 of 89
    Pon’s excluded surrebuttal evidence, which is the assumed error we are talking
    about, had anything to do with any of the eleven patients listed in the indictment or
    the bills he submitted to Medicare for the laser photocoagulation treatment that he
    never administered to those patients.
    b. The Hundreds of Other Patients
    The overwhelming proof of Pon’s guilt did not stop there. There was also
    strong evidence — uninfluenced and unaffected by the partial limitation on Pon’s
    surrebuttal evidence (the assumed error we are talking about) — that Pon
    incorrectly diagnosed and improperly “treated” not just the eleven patients listed in
    the indictment but also hundreds of other patients.
    As discussed, Dr. Friberg testified that almost none of the 500 patients
    whom Pon had diagnosed with WMD actually had the disease. He recounted how,
    during his close review of the files of approximately 500 of Pon’s patients, it was
    “rare” for him to see any indication that any patient had any form of macular
    degeneration — either dry or wet. Only a “very minimal minority” — one or two
    percent — of the 500 patients whose charts he reviewed had any sort of macular
    degeneration. Other eye doctors corroborated Dr. Friberg’s diagnoses for dozens
    of Pon’s patients not named in the indictment.
    Only Pon testified that his WMD diagnoses were correct, and that he
    believed the treatments he administered were helpful and medically necessary. But
    56
    Case: 17-11455     Date Filed: 06/29/2020    Page: 57 of 89
    Pon had strong motivation to say that –– a substantial interest in the outcome of the
    trial. He acknowledged that most of his patients were Medicare beneficiaries and
    that the vast majority of the money he made was from Medicare. If convicted, he
    would lose his medical license and livelihood. And, of course, he faced a prison
    sentence –– ten years as it turned out.
    The jury was entitled to take Pon’s interest into account in evaluating his
    testimony, as it undoubtedly did. We have even held that because a jury is free to
    infer from a testifying defendant’s demeanor that he is not telling the truth, “a
    statement by a defendant, if disbelieved by the jury, may be considered as
    substantive evidence of the defendant’s guilt” when combined with other evidence.
    United States v. Brown, 
    53 F.3d 312
    , 314 (11th Cir. 1995); accord United States v.
    McCarrick, 
    294 F.3d 1286
    , 1293 (11th Cir. 2002) (“In Brown, we held that, in
    combination with other evidence, the jury’s disbelief of a defendant’s testimony
    may be used to help establish his guilt.”); see also United States v. Hough, 
    803 F.3d 1181
    , 1188 (11th Cir. 2015) (“Having seen and heard [the defendant’s]
    testimony, the jury was free to discredit her explanation, to infer that the opposite
    of what she said was true, and to consider that inference as substantive evidence of
    her guilt.”). This is especially true in regard to “highly subjective elements” such
    as “the defendant’s intent or knowledge.” Brown, 
    53 F.3d at 315
    . The jury
    observed Pon for more than three days on the witness stand and had ample time to
    57
    Case: 17-11455     Date Filed: 06/29/2020    Page: 58 of 89
    evaluate his demeanor and credibility. See United States v. Devorso, 
    518 F.3d 1250
    , 1258 (11th Cir. 2008) (“Given the opportunity to evaluate [the
    defendant’s] demeanor and credibility, the jury was entitled not only to disbelieve
    his testimony but, in fact, to find that the opposite of his testimony was true.”).
    The government also offered overwhelming evidence — again, completely
    separate from the assumed error about limiting Pon’s surrebuttal evidence — that
    Pon knew the patients he diagnosed with WMD did not have that disease and knew
    that his micropulse laser technique did not treat that disease. Almost every doctor
    who testified — even Pon himself — said that a person with untreated WMD
    would suffer a substantial decline in the quality of his vision. And yet, the
    evidence at trial showed that Pon abruptly stopped all WMD treatments on at least
    four patients he had diagnosed with WMD and on whom he had been using his
    micropulse laser technique. But Pon continued to treat these patients for other eye
    conditions, so he would have known that the WMD he had diagnosed in them did
    not progress even though they were not receiving any treatment for it, which had to
    mean there was no WMD to begin with and Pon knew it.
    c. Different Treatment for Patients Who Actually Had WMD
    The evidence also showed that Pon used very different WMD treatment
    methods for different patients. Recall the testimony that at the time of Pon’s trial,
    injecting drugs directly into the eye had become the most widely used, accepted
    58
    Case: 17-11455     Date Filed: 06/29/2020   Page: 59 of 89
    treatment for WMD. See supra pp. 4, 14. But evidence at trial showed that Pon
    used those drug injections as a WMD treatment for only some of the patients he
    diagnosed with WMD, at least of those he called as witnesses at trial.
    Significantly, the evidence showed that he used drug injections to treat WMD
    largely, if not only, for those patients whose WMD diagnoses were corroborated
    by another doctor. In other words, he used drug treatments for the rare patients of
    his who actually had WMD. For other patients, ones for whom there was no
    evidence of WMD but he billed as if there were, Pon didn’t use drug injections as a
    WMD treatment or he used it only rarely.
    For example, four of the thirteen patients who testified on Pon’s behalf had a
    WMD diagnosis that had been confirmed by another doctor. Pon gave all four of
    these patients drug injections. For two of these patients, Pon used the accepted
    drug injection treatment as well as his micropulse laser “treatment,” all in the same
    eye. For the other two of these four, he administered injections often and
    consistently, and he never discontinued the injections for either of them. The sum
    of it is that for the few patients whose WMD was confirmed by other doctors, Pon
    treated with the accepted drug injections, as well as his micropulse laser technique,
    and billed for both.
    At least seven of the patients who testified on Pon’s behalf had WMD
    diagnoses from Pon that Dr. Friberg rejected. For these patients, Pon either did not
    59
    Case: 17-11455    Date Filed: 06/29/2020   Page: 60 of 89
    use injections to treat what only he had diagnosed as WMD, or he used injections
    only occasionally. And, as we discussed, for four of these patients, Pon stopped
    administering any WMD treatment — laser or injections — but continued to treat
    them for other eye diseases. That, of course, is evidence that Pon knew those
    patients did not actually have WMD, but he nonetheless diagnosed them with it
    and administered his micropulse laser “treatment,” while billing Medicare under
    code 67220 for laser photocoagulation treatment.
    d. The Ineffectiveness of Pon’s Micropulse Laser “Treatment”
    The government also offered testimony from other doctors — uninfluenced
    by Pon’s excluded surrebuttal evidence — that Pon’s micropulse laser technique
    could not treat WMD and could not coagulate a feeder vessel. One
    ophthalmologist testified that he was “certain far beyond a reasonable medical . . .
    certainty” that Pon’s micropulse laser technique would not close a feeder vessel.
    Another testified that he was not aware of any way that Pon’s micropulse laser
    technique could coagulate a feeder vessel, which was necessary to treat WMD, and
    was what Pon billed Medicare for doing. And yet another ophthalmologist
    testified that there was no way to achieve “subthreshold coagulation” of a feeder
    vessel, as Pon claimed, because those two “terms are mutually exclusive.” And so
    it went.
    60
    Case: 17-11455     Date Filed: 06/29/2020    Page: 61 of 89
    Numerous doctors testified that WMD could not be treated with a laser
    without leaving a scar. Dr. Friberg was “very certain” that using a laser at a power
    high enough to “cook the feeder vessel,” which is how WMD is treated with a
    laser, would leave a mark in the eye. He testified that even if the scars did not
    show up in the eye immediately, “you could see them down the road.” His
    certainty about this came from his experience directing a clinical trial in which the
    doctors “used very minimal laser” and thought they “didn’t leave any marks.” But
    in “[a] month or two,” the patients’ eyes showed signs of scarring.
    Another ophthalmologist had participated in a clinical trial in which the
    doctors attempted to treat dry macular degeneration — which usually precedes
    WMD — using “very, very light laser treatment.” But the trial was stopped early
    because the patients being treated were developing WMD more quickly than their
    counterparts who were receiving no treatment at all. This ophthalmologist testified
    that laser photocoagulating leaking blood vessels, the treatment Pon was billing
    Medicare for, would “by definition, pretty much create a full-thickness burn” and
    leave a scar in the eye. He testified that laser treatment for WMD leaves scars that
    don’t ever completely heal, “and that’s the point actually,” because that is how
    WMD is treated with a laser.
    Other doctors agreed. Another ophthalmologist testified that if a feeder
    vessel had been closed with a laser, “you would see a scar.” And another testified
    61
    Case: 17-11455      Date Filed: 06/29/2020     Page: 62 of 89
    that laser treatment for WMD that has “any kind of effect on the underlying blood
    vessels” would cause “some kind of scar.” And another testified that “the purpose
    of” laser treatment for WMD is to “cook[]” the tissue in the eye, which stops the
    blood vessels from leaking and necessarily results in a visible scar in the eye. And
    another testified that laser treatment for WMD results in “tiny focal laser scars”
    that are generally visible with a standard eye exam and that would always show up
    on a fluorescein angiogram. And yet another testified that “there’s no description
    of [its] being possible” to close a feeder vessel without scarring, and “there’s a lot
    of theoretical and scientific reasons why that would seem extremely unlikely to be
    possible.” Nonetheless, as we discussed, every single doctor who examined the
    eyes of a patient listed in the indictment testified that the patient’s eyes showed no
    indication of the scarring that necessarily accompanies laser photocoagulation —
    the WMD treatment that Pon billed Medicare for administering. See supra pp. 41–
    56.
    e. Filling Out Charts in Advance
    The record also shows that Pon filled out portions of some patients’ charts
    with WMD diagnoses and planned diagnostic tests before he had even seen the
    patients. The government admitted patient notes for three of Pon’s patients who
    had not shown up for a scheduled appointment. Even though Pon didn’t examine
    the patients on the date listed in their charts, parts of their charts were filled out as
    62
    Case: 17-11455     Date Filed: 06/29/2020    Page: 63 of 89
    though he had seen them, including diagnoses and treatment plans. For each of the
    three patients, the prefilled patient notes diagnosed the patient with WMD and
    indicated that fluorescein angiogram and ICG tests (the tests Pon used in making
    his WMD diagnoses) would be performed in both of the patient’s eyes.
    Pon testified that the patient notes were filled out ahead of time likely
    because his technicians were “trying to save time.” He stated that “if anything
    needed to be corrected” after he actually examined the patient, he “would have
    crossed it off” to “make sure everything was consistent with [his] examination.”
    And he identified seven patients whose prefilled notes he had modified to replace
    the diagnosis or treatment plan with one he thought was more appropriate.
    But the government had a response to that. Agent Jurs testified about three
    patients whose prefilled charts Pon had changed to indicate that fluorescein
    angiogram and ICG tests would be done only on one eye (instead of on both eyes,
    as the prefilled charts had originally indicated). For each of those three patients,
    the government introduced an exhibit listing the procedures that Pon had billed
    Medicare for. Those exhibits showed that Pon had billed Medicare for fluorescein
    angiograms and ICGs on both eyes for each of the patients. In other words,
    although Pon had modified the three patients’ prefilled charts to show that those
    tests were done on only one eye, he still billed Medicare as though he had done the
    tests on both eyes.
    63
    Case: 17-11455     Date Filed: 06/29/2020   Page: 64 of 89
    f. The Sound of Silence
    Finally, the record shows that Pon was professionally silent about his
    purported treatment. He acknowledged that he didn’t know of any other doctor
    anywhere who used subthreshold micropulse laser to treat WMD. Yet even though
    he claimed to have discovered a “miraculous treatment” for WMD, he did
    absolutely nothing to present, publish, or even talk with other doctors about what
    he thought of as a cure for the leading cause of irreversible blindness in older
    people. His silence spoke volumes.
    g. Summary
    All of this great volume of evidence we have just recounted was presented
    before and was completely unrelated to and uninfluenced by the exclusion of any
    of Pon’s proposed surrebuttal evidence. And it was that great volume of evidence
    that the government discussed in its closing, not anything about Pon billing
    Medicare for testing he did on J.L.’s blind left eye. In view of the totality of the
    evidence presented, what the jury heard about billing for testing on J.L.’s left eye
    was miniscule. J.L. was one of 34 witnesses who testified at trial, one of fifteen
    who testified for Pon. J.L.’s testimony about the procedures done on his blind left
    eye took up only fifteen pages of transcript. And Agent Jurs’ rebuttal testimony
    concerning that subject, which is what Pon wanted to present surrebuttal testimony
    64
    Case: 17-11455     Date Filed: 06/29/2020    Page: 65 of 89
    about, took up only eleven pages. That’s eleven out of more than 2,000 pages, or
    about one half of one percent, of the testimony that was presented during the trial.
    And it bears repeating that J.L. was not one of the patients listed in the
    crimes charged in the indictment. As we noted, the district court instructed the
    jury that Pon was “on trial only for the specific crimes charged in the indictment,”
    and that it had to determine whether Pon was “guilty or not guilty of those specific
    crimes.” “[T]he Supreme Court has repeatedly held that we must presume that
    juries follow their instructions,” and this Court has “obediently followed” that
    direction. Roy, 855 F.3d at 1186–87 (collecting cases). Following that direction,
    we presume that the jury’s guilty verdict was based on its determination that Pon
    was guilty as charged of fraudulently billing Medicare for laser photocoagulation
    for the eleven patients listed in the indictment, not for fraudulently billing
    Medicare for procedures on J.L.’s blind left eye.
    For all these reasons, we have no doubt, much less a reasonable doubt, that if
    the district court had not partially limited Pon’s surrebuttal evidence about J.L., the
    jury would still have found Pon guilty as charged. The ruling we are assuming was
    an error did not contribute to the jury’s guilty verdict. See Chapman, 
    386 U.S. at 22
    . Any error was harmless beyond a reasonable doubt.
    65
    Case: 17-11455      Date Filed: 06/29/2020   Page: 66 of 89
    5. Our Application of the Harmless Error Rule is Faithful to Precedent
    Our conclusion that the partial limitation on Pon’s surrebuttal testimony was
    harmless beyond a reasonable doubt is in keeping with the Supreme Court’s
    understanding, expressed in Neder, that “[a] reviewing court making th[e]
    harmless-error inquiry does not, as Justice Traynor put it, become in effect a
    second jury to determine whether the defendant is guilty.” 
    527 U.S. at 19
    (quotation marks omitted). And it is consistent with the Court’s description of the
    harmless-error determination as a task done in “typical appellate-court fashion.”
    
    Id.
     Of course harmless error inquiries are typical: “We are, after all, talking about
    ‘the harmless error rule,’ not ‘the harmless error exception.’ Because errorless
    trials are not expected, much less required, harmless error analysis is the rule, not
    the exception.” Roy, 855 F.3d at 1143.
    And for good reason. “The harmless error rule serves vital interests, chief of
    which is conserving scarce judicial resources by avoiding pointless retrials.” Id. at
    1142. And, as we have mentioned, the rule “is also essential to avoid a ‘sporting
    theory of justice’ and a regime of gotcha review.” Id. (quoting Agurs, 
    427 U.S. at 108
    ). The Supreme Court has recognized and relied on these important
    considerations in holding — over and over again — that the harmless error rule
    applies in a wide variety of circumstances. The Court has explained that the
    harmless error rule “promotes public respect for the criminal process by focusing
    66
    Case: 17-11455       Date Filed: 06/29/2020      Page: 67 of 89
    on the underlying fairness of the trial.” Neder, 
    527 U.S. at 18
     (quotation marks
    omitted). It has directed that when “the record developed at trial establishes guilt
    beyond a reasonable doubt, the interest in fairness has been satisfied and the
    judgment should be affirmed.” Rose v. Clark, 
    478 U.S. 570
    , 579 (1986). And it
    has noted that “[r]eversal for error, regardless of its effect on the judgment,
    encourages litigants to abuse the judicial process and bestirs the public to ridicule
    it.” Delaware v. Van Arsdall, 
    475 U.S. 673
    , 681 (1986) (quoting R. Traynor, The
    Riddle of Harmless Error 50 (1970)).
    The Supreme Court has instructed us that “if the defendant had counsel and
    was tried by an impartial adjudicator, there is a strong presumption that any other
    errors that may have occurred are subject to harmless-error analysis.” Rose, 
    478 U.S. at 579
     (emphasis added). The Court has “consistently made clear that it is the
    duty of a reviewing court to consider the trial record as a whole and to ignore
    errors that are harmless, including most constitutional violations.” 10 United States
    v. Hasting, 
    461 U.S. 499
    , 509 (1983) (emphasis added); accord Neder, 
    527 U.S. at
    10
    As the Court’s use of the word “duty” indicates, when the Supreme Court applies
    harmless error analysis to a certain kind of error, it does not merely suggest that we do the
    same — it dictates that we are bound to do so. See, e.g., Mathis v. United States, 
    136 S. Ct. 2243
    , 2254 (2016) (“[A] good rule of thumb for reading [Supreme Court] decisions is that what
    they say and what they mean are one and the same . . . .”); United States v. Johnson, 
    921 F.3d 991
    , 1001 (11th Cir. 2019) (“[W]e must apply Supreme Court precedent neither narrowly nor
    liberally — only faithfully.”); Prison Legal News v. Sec’y, Fla. Dep’t of Corr., 
    890 F.3d 954
    ,
    966 (11th Cir. 2018) (“The only Court that can properly cut back on Supreme Court decisions is
    the Supreme Court itself.”).
    67
    Case: 17-11455     Date Filed: 06/29/2020   Page: 68 of 89
    8 (noting that “most constitutional errors can be harmless” and only “a very limited
    class of cases” evade harmless error review) (quotation marks omitted); Arizona v.
    Fulminante, 
    499 U.S. 279
    , 306 (1991) (noting that “the Court has applied
    harmless-error analysis to a wide range of errors and has recognized that most
    constitutional errors can be harmless”); Van Arsdall, 
    475 U.S. at 681
     (“[W]e have
    repeatedly reaffirmed the principle that an otherwise valid conviction should not be
    set aside if the reviewing court may confidently say, on the whole record, that the
    [error was harmless].”). The Fulminante decision is the paramount example of the
    breadth of the harmless error rule because it held that even where the error was the
    admission of an unconstitutionally coerced confession, courts must still assess the
    totality of the evidence and determine if it was harmless beyond a reasonable
    doubt. See 
    499 U.S. at 310
     (“When reviewing the erroneous admission of an
    involuntary confession, the appellate court, as it does with the admission of other
    forms of improperly admitted evidence, simply reviews the remainder of the
    evidence against the defendant to determine whether the admission of the
    confession was harmless beyond a reasonable doubt.”).
    The Supreme Court has also strictly limited the power of federal courts to
    circumvent a harmless-error inquiry and has rebuked courts who shirk their
    harmless-error review duties. See, e.g., Bank of Nova Scotia v. United States, 
    487 U.S. 250
    , 254 (1988) (“[A] federal court may not invoke supervisory power to
    68
    Case: 17-11455     Date Filed: 06/29/2020    Page: 69 of 89
    circumvent the harmless-error inquiry prescribed by Federal Rule of Criminal
    Procedure 52(a).”); Hasting, 
    461 U.S. at 507
     (stating that the harmless-error
    doctrine “cannot be so lightly and casually ignored in order to chastise what the
    court view[s] as prosecutorial overreaching”).
    We are not saying, of course, that courts shouldn’t be careful with the
    harmless error rule. Courts should be careful in the application of all rules.
    Carelessness is not desirable in any field. But it is not careless to rely on
    overwhelming evidence of guilt to find an error harmless. The Supreme Court
    itself has done it. See, e.g., Neder, 
    527 U.S. at 17
     (“In this situation, where a
    reviewing court concludes beyond a reasonable doubt that the omitted element was
    uncontested and supported by overwhelming evidence, such that the jury verdict
    would have been the same absent the error, the erroneous instruction is properly
    found to be harmless.”) (emphasis added); cf. Yates, 
    500 U.S. at 405
     (describing
    the Chapman harmless-error inquiry as requiring a court to “ask[] whether the
    force of the evidence presumably considered by the jury in accordance with the
    instructions is so overwhelming as to leave it beyond a reasonable doubt that the
    verdict resting on that evidence would have been the same”) (emphasis added).
    And in doing so, the Supreme Court has found errors harmless based on
    overwhelming evidence without displaying special wariness.
    69
    Case: 17-11455     Date Filed: 06/29/2020    Page: 70 of 89
    Our own precedent is thick with decisions finding errors, even serious errors,
    harmless, oftentimes because of overwhelming evidence of guilt. See United
    States v. Esquenazi, 
    752 F.3d 912
    , 931 (11th Cir. 2014), superseded by statute in
    non-relevant part, 
    18 U.S.C. §§ 1956
    , 1957 (finding an error in the trial court’s jury
    instructions harmless “[b]ecause overwhelming evidence support[ed] the jury’s
    finding” of guilt); United States v. Jones, 
    601 F.3d 1247
    , 1264 (11th Cir. 2010)
    (finding the constitutional error the district court allegedly committed harmless
    because even without the error “the government’s case against [the defendant] was
    strong”); United States v. Phaknikone, 
    605 F.3d 1099
    , 1109 (11th Cir. 2010)
    (affirming, in spite of an error, the conviction “in the light of the overwhelming
    evidence of [the defendant’s] guilt”).
    We do that here.
    IV. THE SENTENCE ISSUES
    Pon challenges the procedural reasonableness of his sentence, arguing that
    the district court improperly calculated his guidelines range by erroneously
    applying an 18-level enhancement to his base offense level. The primary issue at
    sentencing was the amount of loss that resulted from Pon’s health care fraud
    scheme. The government said the loss amount was $11.5 million, which would
    result in a 20-level enhancement. See U.S.S.G. § 2B1.1(b)(1)(K) (Nov. 2010)
    (providing for a 20-level enhancement when the total loss amount is more than $7
    70
    Case: 17-11455     Date Filed: 06/29/2020    Page: 71 of 89
    million but not more than $20 million). The district court, however, rejected the
    government’s number and instead estimated the loss amount at $6.97 million,
    which resulted in an 18-level enhancement. See id. § 2B1.1(b)(1)(J) (providing for
    an 18-level enhancement when the total loss amount is more than $2.5 million but
    not more than $7 million). The guidelines range those calculations produced was
    121 to 151 months.
    Pon contends that the district court did not base the loss amount on reliable
    and specific evidence. We review the district court’s loss determination only for
    clear error. United States v. Cobb, 
    842 F.3d 1213
    , 1218 (11th Cir. 2016). For that
    determination to be clearly erroneous, “we must have a definite and firm
    conviction that a mistake has been made.” United States v. Ford, 
    784 F.3d 1386
    ,
    1396 (11th Cir. 2015).
    Under the guidelines, “loss is the greater of actual loss or intended loss.”
    U.S.S.G. § 2B1.1, cmt. n.3(A). Although the district court “may not speculate
    about the existence of facts and must base its estimate on reliable and specific
    evidence, [it] is required only to make a reasonable estimate of the loss.” Ford,
    784 F.3d at 1396. That is “because often the amount of loss caused by fraud is
    difficult to determine accurately.” United States v. Medina, 
    485 F.3d 1291
    , 1304
    (11th Cir. 2007) (quotation marks omitted). And the district court “is in a unique
    position to assess the evidence and estimate the loss based upon that evidence,” so
    71
    Case: 17-11455   Date Filed: 06/29/2020   Page: 72 of 89
    its “loss determination is entitled to appropriate deference.” United States v.
    Campbell, 
    765 F.3d 1291
    , 1301 (11th Cir. 2014) (quoting U.S.S.G. § 2B1.1 cmt.
    n.3(C)).
    Contrary to what Pon says, the district court did base its loss estimate on
    reliable and specific evidence. It considered a spreadsheet that Agent Jurs
    prepared for the sentence hearing, which shows the total amount of money that
    Medicare paid Pon for the thousands of claims he billed on behalf of the patients
    Dr. Friberg determined did not have WMD. The spreadsheet lists each patient’s
    name, the notes that Dr. Friberg took when he reviewed the photos and videos of
    the patient’s eyes, and the number of Medicare claims that Pon had submitted for
    that patient.
    The district court also heard extensive testimony from Agent Jurs, who at the
    time had nearly seventeen years of experience working with Medicare data. He
    testified that the spreadsheet’s total loss amount was accurate because it was
    calculated on a patient-by-patient basis. He also explained that for each of the
    patients Dr. Friberg determined did not have WMD, he “went into the Medicare
    records, pulled the claims that were specific to that [patient], went into
    the diagnosis code section of the claims history, pulled the [WMD] diagnosis code
    that [HHS] knew to be fraudulent and incorrect, and then totaled up only those
    claims, the numbers amount billed and the amount paid for only those claims.”
    72
    Case: 17-11455        Date Filed: 06/29/2020        Page: 73 of 89
    Agent Jurs also testified that the amount billed, the amount paid, and the number of
    actual claims came directly from Medicare’s database.
    That evidence is reliable and it is specific. And based on it, the district court
    made a reasonable estimate of the loss. See Cobb, 842 F.3d at 1218–19. There
    was no error in calculating the loss amount. 11
    There is one other sentence issue. Pon has not raised it, but the government
    has. The district court imposed concurrent 121-month terms of imprisonment on
    each of Pon’s twenty counts of conviction. The government concedes that this was
    error because the statutory maximum penalty for each count is only 120 months.
    See 
    18 U.S.C. § 1347
    (a). We agree, and we commend the government for bringing
    the error to our attention.
    Section 5G1.2(d) of the guidelines provides that where, as here, there are
    multiple counts of conviction,
    [i]f the sentence imposed on the count carrying the highest statutory
    maximum is less than the total punishment, then the sentence imposed
    on one or more of the other counts shall run consecutively, but only to
    the extent necessary to produce a combined sentence equal to the total
    punishment. In all other respects, sentences on all counts shall run
    concurrently, except to the extent otherwise required by law.
    11
    Relying on out-of-circuit decisions, Pon also argues that due process required the
    district court to use the beyond a reasonable doubt standard instead of the preponderance of the
    evidence standard in determining the loss amount. But “it is the settled law of this circuit that at
    sentencing, a federal defendant’s due process rights are . . . satisfied by the preponderance of the
    evidence standard.” United States v. Patti, 
    337 F.3d 1317
    , 1323 n.9 (11th Cir. 2003) (quoting
    United States v. Jackson, 
    57 F.3d 1012
    , 1019 (11th Cir. 1995)).
    73
    Case: 17-11455     Date Filed: 06/29/2020   Page: 74 of 89
    U.S.S.G. § 5G1.2(d). We have interpreted § 5G1.2(d) to require “multiple
    sentences to be served consecutively if the sentence specified by the guidelines is
    longer than the sentence authorized for any individual count of conviction.”
    United States v. Pressley, 
    345 F.3d 1205
    , 1213 (11th Cir. 2003); accord United
    States v. Sarras, 
    575 F.3d 1191
    , 1209 n.22 (11th Cir. 2009) (concluding that
    § 5G1.2(d) remains binding even “[]though the guidelines are now advisory”).
    Those multiple sentences must, of course, run consecutively “to the extent
    necessary to reach the defendant’s guidelines range.” United States v. Johnson,
    
    451 F.3d 1239
    , 1243 (11th Cir. 2006).
    The district court erred in imposing concurrent 121-month terms on each of
    Pon’s twenty counts. While the guidelines specify a sentence of 121 to 151
    months in prison, the statutory maximum for the count with the highest maximum
    (of any of the twenty counts) is 120 months in prison. Because the statutory
    maximum is one month less than the 121-month bottom of the guidelines range,
    § 5G1.2(d) called for at least some of the sentences to run consecutively “to the
    extent necessary to reach [Pon’s] guidelines range” of 121 to 151 months in prison.
    Id. The sentence structure must be modified to reach that range.
    We vacate Pon’s sentences on each count and remand the case to the district
    court for the limited purpose of letting it modify Pon’s sentence structure to bring
    74
    Case: 17-11455       Date Filed: 06/29/2020      Page: 75 of 89
    it in line with § 5G1.2(d). We leave to the court’s discretion how it will do so.12
    Because we do not set aside Pon’s “entire sentencing package” or the time he will
    remain in prison, the modification does not require a resentencing hearing at which
    Pon must be present. See United States v. Tamayo, 
    80 F.3d 1514
    , 1518, 1519
    & n.7 (11th Cir. 1996).
    V. CONCLUSION
    We AFFIRM Pon’s convictions but VACATE his sentences on Counts One
    through Twenty and REMAND the case for resentencing.
    12
    The government has argued on appeal that one of Pon’s twenty 120-month sentences
    should be made to run consecutive to the other nineteen by one month. Pon has not addressed
    that issue. But in any event it’s an issue for the district court to decide.
    75
    Case: 17-11455     Date Filed: 06/29/2020   Page: 76 of 89
    MARTIN, Circuit Judge, concurring in part and dissenting in part:
    Like the majority, I see no abuse of discretion in the District Court’s
    exclusion of David Pon’s expert witness at trial. Nor do I see clear error in the
    District Court’s loss amount calculation. I agree, too, that this Court’s precedent
    forecloses Mr. Pon’s due process challenge to the loss amount calculation. But I
    part ways with the conclusion reached in the majority opinion that any error in
    denying Mr. Pon a surrebuttal was harmless. I believe the denial of a surrebuttal
    violated Mr. Pon’s constitutional right to present a complete defense. And I do not
    believe this error was harmless. Rather than affirm his conviction, I would give
    Mr. Pon a new jury trial. I therefore dissent from the majority opinion’s ruling on
    the harmlessness of any surrebuttal error.
    I.
    “[T]he Constitution guarantees criminal defendants a meaningful
    opportunity to present a complete defense.” Holmes v. South Carolina, 
    547 U.S. 319
    , 324, 
    126 S. Ct. 1727
    , 1731 (2006) (quotation marks omitted). Whether this
    right springs from the fundamentals of due process or from the Sixth Amendment,
    see Crane v. Kentucky, 
    476 U.S. 683
    , 690, 
    106 S. Ct. 2142
    , 2146 (1986), it
    encompasses “the right to present the defendant’s version of the facts as well as the
    prosecution’s to the jury so it may decide where the truth lies.” Washington v.
    76
    Case: 17-11455     Date Filed: 06/29/2020   Page: 77 of 
    89 Texas, 388
     U.S. 14, 19, 
    87 S. Ct. 1920
    , 1923 (1967). This right is not boundless.
    If it were, trials might be never-ending. District courts wield broad discretion to
    control the mode and order of presenting evidence, both to preserve the trial’s
    truth-seeking function and to avoid wasting time. See Fed. R. Evid. 611; United
    States v. Jeri, 
    869 F.3d 1247
    , 1262 (11th Cir. 2017). But this “discretion does not .
    . . extend to the exclusion of crucial relevant evidence necessary to establish a
    valid defense.” United States v. Kelly, 
    888 F.2d 732
    , 743 (11th Cir. 1989)
    (quotation marks omitted).
    When the government presents rebuttal evidence in a criminal case, the right
    to present a defense sometimes requires district courts to allow criminal defendants
    a surrebuttal. See, e.g., United States v. Murray, 
    736 F.3d 652
    , 656–59 (2d Cir.
    2013); United States v. Barnette, 
    211 F.3d 803
    , 821–24 (4th Cir. 2000); United
    States v. Moody, 
    903 F.2d 321
    , 330–31 (5th Cir. 1990). “The purpose of rebuttal
    evidence is to explain, repel, counteract, or disprove the evidence of the adverse
    party.” United States v. Frazier, 
    387 F.3d 1244
    , 1269 (11th Cir. 2004) (en banc)
    (quotation marks and alteration omitted). The same is true of a surrebuttal, except
    that its function is to explain, repel, counteract, or disprove evidence presented in a
    rebuttal. Though narrower in scope than a defense to the government’s case-in-
    chief, surrebuttal nonetheless serves an important purpose. It allows criminal
    defendants to present their version of any new issues that arise in the course of the
    77
    Case: 17-11455       Date Filed: 06/29/2020       Page: 78 of 89
    government’s rebuttal. Juries sometimes cannot “decide where the truth lies” if
    they hear only the government’s side of a rebuttal issue. Washington, 
    388 U.S. at 19
    , 87 S. Ct. at 1923.
    I say Mr. Pon was entitled to a surrebuttal. The rule in this Circuit, as in
    others, is that a “surrebuttal is merited where (1) the government’s rebuttal
    testimony raises a new issue, which broadens the scope of the government’s case,
    and (2) the defense’s proffered surrebuttal testimony is not tangential, but capable
    of discrediting the essence of the government’s rebuttal testimony.” Moody, 
    903 F.2d at 331
    ; see also United States v. Durnin, 
    632 F.2d 1297
    , 1301 n.8 (5th Cir.
    Unit A 1980). 1 Under this standard, this Court’s sister circuits have ruled that the
    Constitution requires a surrebuttal where the government’s rebuttal raised new,
    uncharged allegations of fraud in a fraud case, Moody, 
    903 F.2d at
    330–31,
    advanced a new mental health diagnosis as evidence of future dangerousness to
    support a death sentence, Barnette, 
    211 F.3d at
    821–24, and introduced new
    evidence placing a defendant more frequently in the vicinity of the crime, Murray,
    736 F.3d at 658–59. Rightly so. Without a surrebuttal, the government could use
    rebuttal in those cases both to meet the defense case and to make a new,
    unchallenged case of, respectively, fraud, future dangerousness, and frequent
    1
    In Bonner v. City of Prichard, 
    661 F.2d 1206
     (11th Cir. 1981) (en banc), this Court adopted as
    binding precedent all decisions of the former Fifth Circuit handed down before October 1, 1981.
    
    Id. at 1209
    .
    78
    Case: 17-11455       Date Filed: 06/29/2020       Page: 79 of 89
    presence at the scene of the crime. That result would eviscerate the right to present
    a defense.
    Both conditions for a surrebuttal were plainly met here. The government’s
    rebuttal certainly introduced a new issue about the treatment of J.L.’s left eye for
    conditions wholly unrelated to wet macular degeneration.2 Mr. Pon’s proffered
    surrebuttal testimony about that treatment would have discredited the essence of
    the government’s rebuttal case. Mr. Pon’s right to present his defense required the
    District Court to allow him to testify to his reasons for treating J.L.’s left eye.
    I discern no real dispute about whether the government’s rebuttal evidence
    introduced a new issue. The rebuttal evidence concerned treatment of J.L., a
    patient who testified during the defense case. The substance of J.L.’s testimony
    was that Mr. Pon treated J.L. for detached retinas even knowing J.L. did not have
    insurance, that Pon restored vision in J.L.’s right eye but not his left, and that Pon
    later diagnosed J.L. with wet macular degeneration and treated him with the laser
    method. On cross examination, the government asked J.L. whether Mr. Pon had
    performed any tests on his left eye. J.L. said he had not. J.L. reiterated on redirect
    examination that Mr. Pon hadn’t treated his left eye. After the defense rested, the
    2
    Mr. Pon contends the District Court abused its discretion in allowing a rebuttal. Not so. The
    District Court had discretion to allow the government to rebut the impression J.L.’s testimony
    created of Mr. Pon’s altruism and to clarify J.L.’s treatment history.
    79
    Case: 17-11455        Date Filed: 06/29/2020        Page: 80 of 89
    District Court allowed the government to put on rebuttal, 3 including a spreadsheet
    made by the government’s investigator showing Mr. Pon billed Medicare for
    treating J.L.’s left eye on more than fifty occasions between 2004 and 2015. All
    told, the services added up to $19,350 worth of Medicare charges over eleven
    years.
    Up to the point the government put the spreadsheet into evidence, nothing
    would have indicated to Mr. Pon that he had to defend his reasons for treating
    J.L.’s left eye. For that matter, he would have had no reason to prove that those
    treatments even happened. The government’s case-in-chief revolved around Mr.
    Pon’s false diagnosis and treatment of wet macular degeneration, see Maj. Op. at
    13–16, while the defense case depended on showing Mr. Pon lacked the necessary
    intent to defraud Medicare. With the spreadsheet, the government injected an
    entirely new, unrelated, and uncharged fraud. The clear implication of the rebuttal
    evidence was that Mr. Pon fraudulently billed Medicare not only for diagnosing
    and treating nonexistent wet macular degeneration, but for other procedures as
    well. This broadened the scope of the government’s case. See Moody, 
    903 F.2d at
    3
    The District Court’s decision to allow rebuttal seemed to rest in part on the government telling
    the District Court that it was Mr. Pon who first put the matter in issue by asking about J.L.’s left
    eye on redirect. The District Court sided with the government, believing the defense first asked
    about treatments on J.L.’s left eye on redirect. The government’s representation and the District
    Court’s belief in this regard is contradicted by the record. It was the government who first
    introduced the issue of J.L.’s left eye by inquiring about it on cross-examination.
    80
    Case: 17-11455     Date Filed: 06/29/2020     Page: 81 of 89
    331 (holding the government broadened its fraud case when it brought up new,
    uncharged frauds in rebuttal).
    Nor is there any real disputing that Mr. Pon’s proffered surrebuttal testimony
    would have gone right to the heart of the government’s rebuttal. In his proffer, he
    explained that he did in fact treat J.L.’s left eye and that he had a medical reason
    for doing so—namely, preventing blindness in J.L.’s right eye. This evidence, if
    believed, would squarely rebut the government’s contentions that Mr. Pon never
    treated J.L.’s left eye but billed for it anyway. The limitation of surrebuttal on this
    record violated Mr. Pon’s right to present a defense.
    The government stresses that the District Court limited rather than outright
    denied Mr. Pon’s surrebuttal. And the District Court did allow Mr. Pon to testify
    in surrebuttal that three of the more than fifty entries were the result of a clerical
    error. However, limiting Mr. Pon to this explanation may have exacerbated the
    problem. By allowing Mr. Pon to explain only three of the over fifty treatments,
    the jury may have been left with the impression that Pon had no explanations for
    the remaining treatments. Indeed, the government’s cross-examination of Mr. Pon
    played up the fact that Mr. Pon only had an explanation for “just three entries out
    of two pages of entries.” I question the propriety of this argument by the
    government when it knew Mr. Pon had an explanation for the other entries the
    court forbade him from testifying about. Mr. Pon’s full explanation (treating the
    81
    Case: 17-11455     Date Filed: 06/29/2020     Page: 82 of 89
    left eye helped prevent issues in the right eye) would have rebutted a key
    contention of the government’s rebuttal case. The exclusion of this testimony
    violated the right to present a defense just as surely as a complete denial of
    surrebuttal would have. The limited surrebuttal allowed the government to exploit
    the District Court’s ruling, creating the impression that Mr. Pon had no explanation
    at all for more than forty treatments. In fact he did.
    The short of it is that the District Court allowed the government to inject a
    whole new allegation of fraud into the trial, then hobbled Mr. Pon’s ability to
    respond to it. Mr. Pon had no chance to defend himself against allegations that he
    billed Medicare for treatment he never provided on an eye that couldn’t see.
    Rather than decline to decide the issue, see Maj. Op. at 37–38, I would hold the
    District Court violated Mr. Pon’s constitutional right to present a defense.
    II.
    Not all errors require reversal. This one does.
    Under the harmless error doctrine, this Court will not reverse a district
    court’s constitutional trial error if it is “clear beyond a reasonable doubt that a
    rational jury would have found the defendant guilty” regardless of the error. Neder
    v. United States, 
    527 U.S. 1
    , 18, 
    119 S. Ct. 1827
    , 1838 (1999); see Chapman v.
    82
    Case: 17-11455       Date Filed: 06/29/2020       Page: 83 of 89
    California, 
    386 U.S. 18
    , 24, 
    87 S. Ct. 824
    , 828 (1967). 4 Following the Supreme
    Court’s lead, this Court has identified cases in which “the evidence of the
    defendant’s guilt is ‘so overwhelming’” as “[o]ne circumstance in which courts
    find constitutional errors harmless beyond a reasonable doubt.” United States v.
    Willner, 
    795 F.3d 1297
    , 1322 (11th Cir. 2015) (quoting Harrington v. California,
    
    395 U.S. 250
    , 254, 
    89 S. Ct. 1726
    , 1728 (1969)).
    But the Supreme Court has equally cautioned us to be careful with the
    harmless error doctrine. Take, for example, Neder. It raised the question of
    whether the harmless error doctrine applies in cases where a district court omits an
    element of the offense from the jury instructions. Neder, 
    527 U.S. at 8
    , 119 S. Ct.
    at 1833. The Court held the error “is subject to harmless-error analysis.” Id. at 15,
    119 S. Ct. at 1837. But it warned that courts “should not find [an] error harmless”
    where the defendant contested the omitted element and “raised evidence sufficient
    to support a contrary finding.” Id. at 19, 119 S. Ct. at 1838. Those circumstances
    would, the Court said, preclude the reviewing court from “conclud[ing] beyond a
    4
    As the majority recognizes, the parties dispute which harmless error standard applies. See Maj.
    Op. at 37–38. The government says Mr. Pon did not preserve his constitutional error because he
    did not object on constitutional grounds below. I think the issue was sufficiently preserved. The
    District Court specifically raised Mr. Pon’s Sixth Amendment right to offer an explanation when
    considering whether to grant a surrebuttal. The issue seems to me to “fairly appear[] in the
    record as having been raised or decided” and thus is before the Court. 19 James Wm. Moore et
    al., Moore’s Federal Practice § 205.05(1) (3d ed. 2019).
    83
    Case: 17-11455     Date Filed: 06/29/2020    Page: 84 of 89
    reasonable doubt that the jury verdict would have been the same absent the error.”
    Id.
    It is important to remember that harmless error review is no substitute for a
    jury trial. The Sixth Amendment demands no less. U.S. Const. amend. VI (“In all
    criminal prosecutions, the accused shall enjoy the right to a speedy and public trial,
    by an impartial jury.”). A reviewing court treads on the right to a jury trial when it
    uses harmless error review to “‘become in effect a second jury to determine
    whether the defendant is guilty.’” Neder, 
    527 U.S. at 19
    , 119 S. Ct. at 1839
    (quoting Roger J. Traynor, The Riddle of Harmless Error 21 (Ohio State Univ.
    Press 1970)). And there are practical consequences, too. Whenever we invoke
    harmless error, “the deterrent force of a reversal remains unfelt by those who
    caused the error.” Harry T. Edwards, To Err Is Human, But Not Always Harmless:
    When Should Legal Error Be Tolerated?, 
    70 N.Y.U. L. Rev. 1167
    , 1170 (1995).
    We should be particularly wary of invoking “overwhelming evidence” to
    hold an error harmless. “[T]he Constitution does not trust judges to make
    determinations of criminal guilt.” Neder, 
    527 U.S. at 32
    , 119 S. Ct. at 1844
    (Scalia, J., concurring in part and dissenting in part) (emphasis omitted). The right
    to a jury trial forbids us from doing so. This is why a federal judge may direct a
    judgment of acquittal but never a judgment of guilt. See Rose v. Clark, 
    478 U.S. 570
    , 578, 
    106 S. Ct. 3101
    , 3106 (1986); Fed. R. Crim. P. 29. We owe it to
    84
    Case: 17-11455     Date Filed: 06/29/2020    Page: 85 of 89
    defendants who come before us to ask ourselves always whether a rational jury
    could acquit, and never whether we ourselves think the defendant guilty.
    Taking up this task, I believe a rational jury might have voted to acquit Dr.
    Pon. The majority opinion concludes the government’s evidence against Mr. Pon
    proved beyond a reasonable doubt that “Pon had diagnosed patients with [wet
    macular degeneration] when those patients clearly had never had it” and that Pon
    “billed Medicare for laser photocoagulation treatment of the[se] . . . patients.”
    Maj. Op. at 55. But the government had to prove more than misdiagnosis and
    unnecessary treatment to win a conviction. To win, it had to show Mr. Pon
    intended to defraud Medicare by submitting claims he knew “were, in fact, false.”
    United States v. Crabtree, 
    878 F.3d 1274
    , 1285 (11th Cir. 2018) (quotation marks
    omitted); see also Pattern Crim. Jury Instr. 11th Cir. O53 (2019). The focus on
    whether there was any doubt that the patients named in the indictment had wet
    macular degeneration or needed laser treatment elides this point.
    Of course, I do not contend the evidence the government presented about
    Mr. Pon’s diagnoses and treatments lacked probative value. The evidence of
    misdiagnosis and unnecessary treatment supplied circumstantial evidence of Mr.
    Pon’s intent, and enough of it to support a conviction. See United States v. Clay,
    
    832 F.3d 1259
    , 1309 (11th Cir. 2016); United States v. Bradley, 
    644 F.3d 1213
    ,
    85
    Case: 17-11455     Date Filed: 06/29/2020   Page: 86 of 89
    1239 (11th Cir. 2011). But Mr. Pon also met the government’s case with enough
    evidence to support an acquittal, had the jury so decided.
    Mr. Pon spent more than three days on the stand. At the outset, he testified
    he “absolutely [did] not” intend to defraud Medicare. He spent the next several
    days explaining in granular detail how he diagnosed and treated patients. He said
    he got the idea for his diagnostic method from a talk given by Dr. Robert Murphy,
    a leading ophthalmologist. Dr. Murphy proposed using an emerging technology to
    visualize “occult neovascularization”—essentially, new, difficult-to-see blood
    vessels forming in the eye. Mr. Pon said he thought the technique was “the
    greatest thing since sliced bread, because this technology was going to allow direct
    visualization of those tiny, tiny little blood vessels.” Mr. Pon said he believed
    based on Dr. Murphy’s presentation that he could detect wet macular degeneration
    in its earliest stages using a cutting-edge technique.
    As for treatment, Mr. Pon said he got some ideas about that from Dr.
    Murphy’s presentation, too. Dr. Murphy reported using a laser to create a “thermal
    gradient”—a heat differential—in the eye to close the feeder vessels that caused
    wet macular degeneration. This technique did not cause scarring, as do traditional
    laser techniques for treating wet macular degeneration. Dr. Pon also thought this
    was “the greatest thing since sliced bread.”
    86
    Case: 17-11455     Date Filed: 06/29/2020   Page: 87 of 89
    Mr. Pon bought the equipment he believed he needed to put Dr. Murphy’s
    diagnostic and treatment techniques into practice. He later upgraded the
    equipment with a purchase he explained he would not have made if his intent had
    been to defraud. Mr. Pon began treating patients with it and said he found lower
    power settings provided better results than Dr. Murphy’s thermal-gradient method.
    And the jury didn’t have to take Mr. Pon’s word for it. Mr. Pon called
    twelve of his patients and the spouse of another to testify that the lasers improved
    their (or her spouse’s) vision. One witness, who has advanced public health
    degrees and background as a nurse, testified she learned from Mr. Pon to identify
    feeder vessels on a diagnostic monitor during Pon’s treatment of her husband, who
    Pon diagnosed with wet macular degeneration. Another, a laser nurse, likewise
    testified she could see the problem areas Mr. Pon identified and that her vision
    improved with laser treatments. The government agreed some of these thirteen
    patients actually had wet macular degeneration. It disagreed as to others. But for
    all the patients who testified for Mr. Pon, their testimony was uniform that Mr.
    Pon’s laser treatment helped.
    With this evidence before it, a rational jury could acquit Mr. Pon. This
    hypothetical acquitting jury could do so without any belief that: (1) Mr. Pon indeed
    diagnosed his patients with wet macular degeneration no one else could see or (2)
    treated it using miraculous new technologies in ways no other doctor could. Yet
    87
    Case: 17-11455     Date Filed: 06/29/2020   Page: 88 of 89
    these are the two issues the majority opinion focuses on. To acquit, a jury would
    have to conclude only that Mr. Pon believed in good faith he could do these things.
    His own testimony and that of his patients, some of whom even the government
    admits had wet macular degeneration, would suffice for a rational jury to believe
    Mr. Pon acted in good faith. If a patient who couldn’t read a menu before says he
    can after a doctor gave him a laser treatment, reasonable people could agree the
    doctor believed the treatment worked. I do not dispute that reasonable jurors could
    also convict Mr. Pon. But the government’s evidence of intent, as distinct from the
    evidence that Mr. Pon misdiagnosed and unnecessarily treated his patients, is not
    so overwhelming that this Court should affirm the judgment of guilt.
    The case for acquittal would have been even stronger if Mr. Pon had the
    chance to give his full surrebuttal. The government’s rebuttal evidence was highly
    prejudicial, or “very damning,” as the District Court saw it. In a case all about Mr.
    Pon’s intent, the government’s rebuttal certainly created the impression that Mr.
    Pon either 1) billed Medicare for treatments he never provided, or 2) billed
    Medicare for dozens of useless treatments on a blind eye. And then the
    government nailed Mr. Pon during his surrebuttal, emphasizing how limited an
    explanation he gave, just three entries, in the face of a spreadsheet showing years
    of treatments. The government implied Mr. Pon had nothing to say about the other
    entries, when of course it knew he had an explanation. The jury may well have
    88
    Case: 17-11455     Date Filed: 06/29/2020    Page: 89 of 89
    taken this as essentially a confession to an unrelated fraud. A “defendant’s own
    confession is probably the most probative and damaging evidence that can be
    admitted against him.” Arizona v. Fulminante, 
    499 U.S. 279
    , 296, 
    111 S. Ct. 1246
    ,
    1257 (1991) (quotation marks omitted).
    Between the spreadsheet and the limited surrebuttal, so far as the jury knew
    Mr. Pon had no explanation at all for treating a blind eye. And so far as we know,
    the jury went back to their deliberations thinking Mr. Pon was a crook because of
    it. A rational jury allowed to hear the case with Mr. Pon’s explanation could
    render a different verdict than this one did. That being the case, I must say this
    error was harmful. I believe Mr. Pon should get a new trial.
    III.
    I believe a second jury should have decided Mr. Pon’s guilt or innocence.
    For this reason, I dissent from the majority opinion’s holding that any error in Mr.
    Pon’s case was harmless.
    89