United States v. Chisholm ( 2019 )


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  •           United States Court of Appeals
    For the First Circuit
    No. 17-1952
    UNITED STATES OF AMERICA,
    Appellee,
    v.
    DENZEL CHISHOLM, a/k/a Den, a/k/a Din,
    Defendant, Appellant.
    APPEAL FROM THE UNITED STATES DISTRICT COURT
    FOR THE DISTRICT OF MASSACHUSETTS
    [Hon. Patti B. Saris, U.S. District Judge]
    Before
    Thompson, Kayatta, and Barron,
    Circuit Judges.
    Jin-Ho King, with whom Leonard E. Milligan III and Milligan
    Rona Duran & King LLC were on brief, for appellant.
    Alexia R. De Vincentis, Assistant Attorney General, with whom
    Andrew E. Lelling, United States Attorney, was on brief, for
    appellee.
    October 8, 2019
    THOMPSON, Circuit Judge.
    OVERVIEW
    Of the seventeen people indicted in this drug case, fifteen
    pled guilty and two stood trial together — the two being Denzel
    Chisholm and Molly London.      At the trial's end, the jury convicted
    Chisholm of a variety of offenses, including conspiring to possess
    heroin with intent to distribute, plus possessing and distributing
    heroin   (these   counts   of   conviction      also   charged    aiding-and-
    abetting liability) — though the jury acquitted him of being a
    felon in possession of a firearm.              The jury also found that
    prosecutors proved beyond a reasonable doubt that the conspiracy
    involved 1 kilogram or more of heroin and that this amount "was
    attributable to and reasonably foreseeable" to him — to establish
    that number, prosecutors relied on evidence from controlled buys,1
    non-controlled         seizures,        intercepted         communications,
    surveillance, and cooperating witnesses.          As for London, the jury
    convicted   her   of   maintaining     an     apartment   for    storing   and
    distributing heroin, plus possessing and distributing heroin (the
    last count of conviction charged aiding-and-abetting liability as
    1  A controlled buy is when a confidential informant or
    undercover agent uses money from the government to buy drugs as
    part of an investigation. See, e.g., United States v. Jordon, 
    999 F.2d 11
    , 12-13 (1st Cir. 1993).
    - 2 -
    well).    And the district judge later handed out prison sentences
    of 342 months to Chisholm, and 20 months to London.
    Only Chisholm's appeal is before us.2   And he challenges
    both his convictions and sentence.      On the convictions front, he
    contends that the judge slipped by denying two mistrial motions —
    the first based on the judge's allowing a government witness to
    retake the stand and recant some trial testimony, and the second
    based on London's supposedly offering a defense prejudicially
    antagonistic to his own.    On the sentencing front, he claims that
    the judge substantively erred by imposing a sentence beyond what
    Congress intended for the type of drug transactions that went down.
    The government thinks that nothing here rises to the level of
    reversible error.    We do too and affirm.
    MISTRIAL-DENIAL CLAIMS
    Background
    The salient events are not disputed (buckle in, because
    we have a lot of ground to cover — even though we recount only
    what is needed to understand the issues on appeal).
    During pretrial discussions about evidentiary issues
    that might arise if London chose to testify, London's lawyer told
    the judge that her defense would be that "she was unaware of
    2   London moved to withdraw her appeal, which we granted.
    - 3 -
    [Chisholm's] activity in [her] house."            Asked by the judge if she
    planned on "pointing [her] finger . . . at Chisholm as [a] bad
    guy," London's lawyer replied that her "defense is that she was
    being taken advantage of; she was betrayed by her best friend who
    used her."      That is an "issue," the judge said.            And then the judge
    asked how things could be "fix[ed] . . . if she takes the stand
    and points a finger at Chisholm."          London's counsel clarified that
    London "can't say that she knew" the heroin "was Chisholm's because
    she    didn't    know   it   existed   there."      And       given    how   counsel
    "rephrased it," the judge saw no need to sever Chisholm from London
    for trial.      Neither did Chisholm's lawyer.
    Jumping to opening statements at trial, we see that the
    prosecutor told the jury that "Chisholm was the leader of the
    largest heroin-trafficking organization on Cape Cod."                   He and "his
    childhood friends, Christopher Wilkins and Christian Chapman[,]
    . . . pooled money to buy large quantities of pure heroin, which
    they    divided    among     themselves   and    sold    to    their    respective
    customers" — all while "stor[ing] their heroin and their drug-
    trafficking tools at various residences," including London's.                   The
    prosecutor then explained that four categories of evidence would
    seal Chisholm's and London's fate:              drug-dealer testimony, like
    from   "Ricky     Serriello";    law-enforcement        testimony      "describing
    their investigation"; recorded calls and videos made by another
    - 4 -
    cooperating dealer; and "physical evidence" seized from Chisholm's
    and London's homes.
    Chisholm's lawyer told the jury in his opening that
    "[i]t's true that [Chisholm] and friends and people he grew up
    with were drug dealers."       So, he added, "what this trial is really
    about is the weight and scope of the conspiracy."              Counsel then
    painted a picture of "a group of childhood friends who . . . became
    small street-level drug dealers" — apparently in an attempt to
    cast doubt on the amount of heroin properly attributed to him.
    In her opening, London's lawyer told the jury that "Molly
    London had no idea that Denzel Chisholm was selling drugs," because
    "[h]e took pains to hide his conduct from Molly."             London had no
    clue that Chisholm hid heroin in her house, counsel later stressed,
    "because [he] took advantage and betrayed her trust over and over
    again."   Chisholm's attorney did not object to London's lawyer's
    opening statement.
    The government then called its first witness, Serriello.
    Asked "[w]ho supplied you with the heroin you were caught with,"
    he responded, "I don't really remember."           He also claimed that he
    did not remember testifying before the grand jury, speaking with
    law-enforcement     agents,    or    giving    a   proffer    outlining    his
    anticipated testimony.        Confronted with a copy of his grand-jury
    testimony,     Serriello   said     that    "[m]aybe   [he]   was   high    or
    - 5 -
    something," because he "d[idn't] remember saying any of this."
    Asked specifically about his grand-jury statement that Chisholm
    had supplied the heroin, he stated, "The Denzel Chisholm I know
    isn't in this courtroom right now."
    Chisholm's       lawyer    requested     a    sidebar    conference.
    Talking with counsel, the judge told them that Serriello and
    Chisholm "nodded to each other" as they (counsel) were heading
    toward the bench.       "It's clear," the judge added, "that either
    someone got to [Serriello] or he's terrified."             After excusing the
    jury, the judge asked Serriello — in Chisholm's presence — if
    anyone had threatened him.           "No," he replied.      Chisholm's lawyer
    then questioned Serriello and confirmed that Chisholm had not
    threatened him.       And the judge confirmed that his testimony was
    that "there is a human being named Denzel Chisholm who sold
    [Serriello] drugs, but it isn't the guy here."               Weighing in, the
    prosecutor said that Serriello was "clearly perjuring himself,"
    because "[h]e spoke with us yesterday" and had identified Chisholm
    by photograph.    And "[h]e'll probably be indicted for perjury."
    The next morning, the judge revealed at sidebar that
    Serriello's lawyer had said that "there was a threat to kill Mr.
    Serriello's child."         Over Chisholm's counsel's objection, the
    judge   said   that   she   would    conduct   an   ex   parte     hearing   with
    Serriello and his attorney during a break in the trial.
    - 6 -
    The government then put Stephanie Davis on the stand.      A
    onetime conspiracy member turned government cooperator, Davis
    called Chisholm "the biggest drug dealer" she knew.       For a time,
    Chisholm and Wilkins came to her apartment once a week with 10 to
    30 grams of raw heroin, which they would "cut" (i.e., make less
    pure) and press into "bricks" containing "a couple of hundred
    grams" of finished product.      Davis also testified that Chisholm
    sold heroin knowing that it caused people to overdose.
    Chisholm's   counsel   attacked   Davis's    credibility   on
    cross-examination — focusing, for example, on how she "was a drug
    dealer in this group of drug dealers" and had failed a drug test
    just a few months earlier.    As for London's lawyer, she got Davis
    to agree that a "core" group of drug dealers, a "triad," had worked
    together here — Chisholm, Chapman, and Wilkins.       "[T]hey were the
    big players[,] . . . the ones that you regularly interacted with,"
    London's attorney said, to which Davis responded, "Yes."      And when
    London's counsel asked if "within that circle, there were other
    people [—] either individuals that ran stash houses, addicts who
    would use and then sell to use, or sell to use and profit [—]
    underneath them," Davis answered, "Uh-huh."
    After Davis left the stand, Chisholm's lawyer objected,
    saying that "in a pretrial hearing, we were very clear about
    evidentiary limits on Ms. London's eventual defense" and that
    - 7 -
    "we're treading awfully close to the issues we . . . discussed."
    The judge opted to defer ruling on that issue, however.   And then
    she held the ex parte hearing with Serriello and his lawyer.
    About a half-hour later, the judge reported back that
    Serriello had said that he had gotten some threats involving his
    daughter from third parties (he did not get names, though).    And
    he was afraid something might happen to him in prison.     He also
    explained that he became nervous on the stand after hearing a
    clicking sound, as if someone in the courtroom had taken his
    picture — which is why he had testified the way he did.     But he
    now wanted to testify again.
    Chisholm's attorney objected to any ruling allowing the
    government to recall Serriello, saying "[t]here's vast prejudice
    to [Chisholm]" if the judge let Serriello rehabilitate himself by
    testifying "that he was intimidated into not testifying" the first
    time.   But the judge indicated that she would let prosecutors put
    Serriello back on the stand and ask one or two questions about the
    reason for his changed testimony — though they could not mention
    that the threat involved his daughter, because that info was too
    prejudicial.   Chisholm's lawyer asked for a mistrial, arguing that
    there was "zero evidence of [his client's] participation" in the
    threats, yet the jury would have "no choice but . . . to infer
    that [he] procured that." Implicitly denying the motion, the judge
    - 8 -
    said that she would instruct the jury "that there's no evidence"
    that any threat "was done at [Chisholm's] request."
    On the stand a second time, Serriello testified that he
    had lied the day before because he perceived a threat from a "third
    party."     He also fingered Chisholm as his main dealer, from whom
    he had gotten the 400 grams of heroin found on him when arrested.
    And he said that he had bought heroin from Chisholm for about a
    year, at one point buying 500 grams on a weekly basis.                      Cross-
    examined by Chisholm's lawyer, he admitted that he had not seen or
    heard from Chisholm since his (Serriello's) arrest; that he was
    not   saying    that     Chisholm    had   threatened   him;     and   that   law-
    enforcement agents had reminded him "in a roundabout way" that
    testifying falsely put his plea deal in jeopardy.
    The       following   morning,    Chisholm's    attorney       filed   a
    mistrial motion.          In his accompanying memo, counsel wrote that
    Serriello's recall testimony suggested to the jury that "Chisholm,
    someone at his command, or someone seeking to assist him threatened
    . . . Serriello for taking the stand against . . . Chisholm" —
    which among other things might lead the jury to conclude "that a
    conspiracy exists because the third-party who threatened . . .
    Serriello      must    have   some   arrangement   .    .   .   to   try   helping
    [Chisholm]."      Also according to counsel, Serriello's testimony was
    so highly prejudicial as to be incurable by any instructions from
    - 9 -
    the judge.       Shifting focus, counsel then argued that "London's
    opening statement and cross-examinations exceed[ed] the scope of
    the parties and the [judge's] understanding of . . . London's
    defense."    "Chisholm did not insist on separate trials," counsel
    noted, "because he expected . . . London's trial defense to be one
    of lack of knowledge"; but London ended up "point[ing] a finger "
    at   him   and   "us[ing]   the   term   'triad[,]'"   a    word   "linked    to
    organized crime" — all of which "unduly" prejudiced him.
    The judge did not want to rule from the bench, however.
    But she did give the jury a limiting instruction, explaining that
    Serriello's testimony about a "perceived threat"
    can only be used to assess the credibility of . . .
    Serriello, whether you believe him or not why he changed
    his testimony. You cannot use that in any way against
    . . . either of the defendants, but in particular . . .
    Chisholm, because there's no evidence he made that.
    Prosecutors continued parading witnesses and presenting
    physical    evidence   (recorded     audio   and   video,    pages   of   text
    messages, etc.) against Chisholm and London.           And they also filed
    a multifaceted objection to Chisholm's mistrial motion.                      For
    starters, they pointed out that Serriello admitted on the "stand
    that he was not accusing . . . Chisholm of threatening him."                 And
    given the government's evidence — involving, for example, many
    cooperators, calls and text messages, police surveillance, and
    controlled heroin buys — Chisholm cannot show that "one witness'[s]
    - 10 -
    testimony" (from the very first witness to testify) "so taint[ed]
    the jury as to mandate a mistrial."                 As for Chisholm's problem
    with     London's   strategy,        prosecutors        spotted     no    troubling
    antagonism,     seeing    how   he    "conceded      his   involvement      in   drug
    trafficking" and his "defense in no way hinges" on the notion that
    she knew about "his drug trafficking."                     Turning to London's
    lawyer's use of "triad," prosecutors saw no need for a mistrial —
    yes, the word can "refer to Chinese organized crime groups in
    certain contexts"; but the word has many meanings, including "a
    union or group of three" (or so their argument went).
    London's lawyer argued to the judge that she had been
    "very transparent" that London's defense would be that London did
    not know heroin was in her apartment or who put it there.                        But,
    counsel continued, "the evidence is overwhelming that the only
    logical    person   who    could     have   put    it   there     would   have   been
    [Chisholm]."
    Taking up Chisholm's motion, the judge said that she had
    never heard "triad" used "in connection with a gang."                       And she
    denied    his   mistrial    request     for    the      reasons    stated   in    the
    government's memo.
    Throughout      all       this,       London's      lawyer's     cross-
    examinations generally focused on how the witnesses did not know
    London or if they did, how they had done their drug business at
    - 11 -
    her house outside her presence.          Her lawyer also questioned ATF
    Special Agent Christopher Kefalas about locations Chisholm used to
    cut and stash heroin — all in the hopes of drawing a distinction
    between Chisholm's need to coordinate access to London's home and
    what counsel suggested was Chisholm's unfettered access to these
    other houses.3     And in her direct and cross-examinations, London
    testified that she never saw anything in her home that made her
    think that anyone was buying or selling heroin there.
    Turning to closing arguments (and we're only hitting the
    highlights), we note that the prosecutor told the jury that it
    "should be very skeptical of what Mr. Serriello had to tell you"
    and   "shouldn't    take    his   word   without   highly   corroborating
    evidence."      "But here," the prosecutor said, "we have that,"
    pointing to the evidence gathered by criminal investigators.            And
    about the recall testimony, the prosecutor just said that Serriello
    "explained the reason for his lies, and I think the evidence shows
    that he was telling the truth."
    Chisholm's    lawyer's   closing   argument    portrayed   his
    client as a man who owned no house, car, or jewelry and had less
    than 10 grand in cash — hardly the profile of a bigtime drug
    3"ATF" is an acronym commonly used for the Bureau of Alcohol,
    Tobacco, Firearms and Explosives.
    - 12 -
    dealer.      And    he   insisted     that   government's          case    rested    on
    exaggerations and untruths.
    Repeating     her     opening       statement     a    bit,    London's
    attorney's    closing     argument       focused    on   the   deception       theme.
    Chisholm,    her    lawyer   said,       "used    [London's]       friendship,      her
    kindness, and he preyed on her gullibility, and he did it with a
    false commitment of friendship . . ., a deception used by a highly
    skilled drug dealer." Counsel also emphasized the "huge difference
    between the real members who were operating stash houses and Molly
    London."     And when Chisholm's attorney moved for a mistrial based
    on the closing, the judge responded at sidebar, "Let me just say,
    I keep denying it because you can see that he's a drug trafficker."
    The    prosecutor's      rebuttal     argument        emphasized    that
    Chisholm was "a wide-scale heroin dealer" who "didn't hide himself
    from [London]."
    Which brings us to today, with Chisholm again saying
    that he deserved a mistrial because Serriello's recall "threat"
    testimony     "created     an      inescapable      inference       that    unfairly
    inculpated" him (Chisholm) in the drug conspiracy, and because
    London's "antagonistic" shift in her defense prejudiced him by
    undercutting       his   ability    to    muster    a    proper     defense.        The
    government thinks otherwise, arguing that the "adverse" inference
    Chisholm believes the jury would draw from Serriello's recall
    - 13 -
    testimony was "not so compelling," and that "the tension between
    his defense and London's was not so severe," as to make "the jury
    impervious" to the judge's instructions about "the limited purpose
    for which it could consider Serriello's testimony about the threat"
    and its duty "to consider separately the evidence against each
    defendant."
    Standard of Review
    Ordering a mistrial is a last-resort remedy, "only to be
    implemented if the taint is ineradicable, that is, only if the
    trial judge believes the jury's exposure to the [complained of]
    evidence is likely to prove beyond realistic hope of repair."
    United States v. Sepulveda, 
    15 F.3d 1161
    , 1184 (1st Cir. 1993).
    And we review a district judge's denial of a mistrial motion only
    for "manifest abuse of discretion," because she is in the best
    position to decide if an incident is sufficiently serious to
    justify the drastic step of terminating a trial. See, e.g., United
    States v. DeCologero, 
    530 F.3d 36
    , 52 (1st Cir. 2008) (emphasizing
    that district judges are "better enable[d] . . . to strike the
    delicate balance between fending off prejudice, on the one hand,
    and husbanding judicial resources, on the other hand" (internal
    quotation marks omitted)).   Which is why "it is only rarely — and
    in extremely compelling circumstances — that [we], informed by a
    cold record, will venture to reverse a trial judge's on-the-spot
    - 14 -
    decision" that the interests of justice do not require aborting an
    ongoing trial.         United States v. Georgiadis, 
    819 F.3d 4
    , 16 (1st
    Cir. 2016) (quoting United States v. Freeman, 
    208 F.3d 332
    , 339
    (1st Cir. 2000)); accord United States v. Butterworth, 
    511 F.3d 71
    , 76 (1st Cir. 2007).
    Analysis
    Serriello's Recall Testimony
    First up is Chisholm's claim that the judge should have
    granted a mistrial after Serriello retook the stand and testified
    about the threat he had received.4                Let's put to one side that
    Serriello explicitly said that Chisholm did not threaten him.                See
    generally United States v. Pérez-Montañez, 
    202 F.3d 434
    , 439 (1st
    Cir. 2000) (finding evidence about a threat admissible to show a
    witness's "motivation for having changed his version of events").
    Like       the   government,   we   think   the    prejudicial   inference   he
    complains about — that the jury would have speculated either that
    4
    Although framed as a challenge to the mistrial denial,
    Chisholm sprinkles into his briefing some cites to Rules of
    Evidence 403 and 404(b) — generally speaking, Rule 403 excludes
    probative evidence that is substantially outweighed by its
    prejudicial effect, and Rule 404(b) bars evidence of a defendant's
    other offenses to show that his actions conformed to his bad
    character. See, e.g., United States v. Rivera-Carrasquillo, 
    933 F.3d 33
    , 46 (1st Cir. 2019). But whether viewed as an error in
    admitting evidence or in denying a mistrial, the standard of review
    is abuse of discretion. See United States v. Dunbar, 
    553 F.3d 48
    ,
    59 (1st Cir. 2009); United States v. Bradshaw, 
    281 F.3d 278
    , 284
    (1st Cir. 2002).
    - 15 -
    he made the threat because he was guilty as charged and wanted to
    avoid getting convicted or that he "inhabited a sufficiently
    important role within the drug-trafficking organization to obtain
    such dramatic intervention" — is not so strong as to defy repair
    short of a mistrial.
    For one thing, the record contains no evidence of any
    violence by Chisholm to support the suggestion that the threat
    came from him — the jury found him not guilty of a firearms charge,
    and    the   jury's       discriminating   verdict   shows   that   Serriello's
    recall testimony did not (as Chisholm claims) "serve[] as an
    unspoken appeal to fears of gang violence" and "drug trafficking
    organizations."           For another thing, the threat could have come
    from    anyone,       including    a   family   member,      a   friend,   or    a
    coconspirator.        And given the thinness of the alleged prejudicial
    inference, the judge's telling the jury not to use Serriello's
    perceived-threat testimony against Chisholm or London "was the
    right course" under our caselaw.           See 
    Butterworth, 511 F.3d at 76
    .
    Butterworth devastates Chisholm's argument.               There, a
    cooperating coconspirator in a drug case claimed (incorrectly,
    apparently) that he was testifying in exchange for government
    protection.         
    Id. Defendant Butterworth
    moved for a mistrial,
    arguing that the statement implied that he had threatened the
    witness.      
    Id. The district
    judge denied the motion.            
    Id. We -
    16 -
    affirmed, calling the prejudicial inference "thin[]," because
    "there was no evidence of violence by Butterworth elsewhere in the
    trial and any threat could have come from a [drug] supplier," and
    noting that the judge had given a "swift and clear curative
    instruction" to the jury that "there is no evidence that . . .
    Butterworth has made any threats on the [cooperator's] life" and
    to "disregard the statement."    
    Id. Chisholm tries
    to distinguish Butterworth on the ground
    (emphasis ours) that "the evidence" there "merely implied the
    existence of a threat" while prosecutors here "explicitly put in
    evidence that someone threatened . . . Serriello into lying."   Why
    this should make a difference escapes us.    And that is because,
    given the government's alleged protection offer in Butterworth, a
    jury could have easily concluded that someone there had (as here)
    threatened the cooperator into lying — a situation that required
    no mistrial, for the reasons just discussed.5
    5 Pulling out all the stops, Chisholm also calls Serriello's
    "live testimony" unnecessarily "cumulative."      As support, he
    points to a recorded statement where he talked to a "Darren
    Pelland" about selling Serriello like a "half a brick" a week.
    But we agree with the government that Serriello's testimony helped
    corroborate Chisholm's recorded statement (a statement that
    Chisholm's lawyer tried to pass off below as mere puffery) —
    meaning the cumulative-evidence claim is also a no-go.
    - 17 -
    Ultimately,      then,    the   judge's   denial   of   Chisholm's
    mistrial    motion   based    on     Serriello's   recall    testimony   passes
    abuse-of-discretion review.
    London's Defense Strategy
    Next up is Chisholm's claim that the judge should have
    granted a mistrial because London's switch in trial tactics made
    their defenses "irreconcilably antagonistic," demonstrating a risk
    of prejudice that required a mid-trial severance.              The government
    completely disagrees, asserting that any "tension" between their
    defenses "was not so severe" as to make his trial unfair.                Again,
    we side with the government.
    Defendants indicted together ordinarily may be tried
    together.    See, e.g., Zafiro v. United States, 
    506 U.S. 534
    , 537
    (1993).     That a defendant thinks his chances for acquittal would
    be better in a separate trial is not enough to order a mid-trial
    severance or a mistrial.             See 
    id. at 540.
           Neither remedy is
    required just because the defendants have "mutually antagonistic
    or irreconcilable defenses," see 
    id. at 538
    — "[f]inger-pointing
    among the defendants," for instance, "is not only acceptable but
    also a benefit of a joint trial, for it helps the jury to assess
    the role of each defendant," see United States v. Hoover, 
    246 F.3d 1054
    , 1061 (7th Cir. 2001).          Rather, to justify the "extraordinary
    measure" of a mid-trial severance, a defendant must show that the
    - 18 -
    joint trial caused him such compelling prejudice that he was robbed
    of a fair trial, see United States v. Sotomayor-Vázquez, 
    249 F.3d 1
    , 17 (1st Cir. 2001) (quotation marks omitted) — like when "the
    antagonism [is] such that if the jury believes one defendant, it
    is compelled to convict the other defendant," see United States v.
    Floyd, 
    740 F.3d 22
    , 36 (1st Cir. 2014) (quotation marks omitted);
    see also 
    Zafiro, 506 U.S. at 539-41
    .               This is a very high bar.
    See 
    Sotomayor-Vázquez, 249 F.3d at 17
    . And it is one that Chisholm
    cannot clear.
    The gist of London's defense — and what she testified to
    — was that she did not know Chisholm sold heroin.                  Chisholm does
    not   claim    that   this    aspect    of   her   defense    is   prejudicially
    antagonistic.       Nor could he.      What he argues is that her lawyer's
    suggestion      —   pushed    in   opening      statements,    cross-examining
    witnesses, and closing arguments — that he "was a large-scale,
    sophisticated heroin trafficker" made her defense prejudicially
    antagonistic to his.          But the problem for him is that the jury
    could believe — or (as it did here) disbelieve — both London's
    claim of ignorance and Chisholm's denial of the conspiracy's
    existence and scope:         she claimed no knowledge of his drug-dealing
    activity (on whatever scale), and so whether he dealt in large
    quantities was peripheral to her defense.
    - 19 -
    On top of that, courts measure "the level of antagonism
    . . . by the evidence actually introduced at trial." United States
    v. Rose, 
    104 F.3d 1408
    , 1416 (1st Cir. 1997) (emphasis added).
    And "argument by counsel is not" — repeat, not — "evidence."   Id.;
    accord United States v. Tiem Trinh, 
    665 F.3d 1
    , 18 (1st Cir. 2011).
    Which takes care of Chisholm's arguments based on counsel's opening
    and closing statements.
    As for Chisholm's arguments based on counsel's cross-
    examination questions, the testimony elicited merely echoed the
    evidence already introduced by the government.       For instance,
    before testifying on cross that Chisholm was among the "big
    players" that she "regularly interacted with," Davis testified on
    direct that Chisholm (working with Wilkins and Chapman) visited
    her home weekly to cut and bag vast amounts of heroin, used her
    and others' homes as stash houses, and used her and others to sell
    drugs.   Also, the distinction counsel tried to draw when cross-
    examining Special Agent Kefalas (between Chisholm's access to
    other stash houses and London's house) was premised on already-
    admitted evidence that Chisholm used others' homes to hide drugs.
    And by essentially being "a reaffirmation" of the prosecution
    witnesses' direct testimony — "neither adding to, nor subtracting
    from," the prosecution's "case" — the complained-of cross does not
    help Chisholm's claim.    See United States v. Peña-Lora, 225 F.3d
    - 20 -
    17, 34 (1st Cir. 2000) (quotation marks omitted); see also United
    States v. Tejeda, 
    481 F.3d 44
    , 55-56 (1st Cir. 2007) (holding that
    even though the defendant denied being the conspiracy's drug source
    and a codefendant identified him as a drug supplier, the defenses
    were not so antagonistic as to require a mid-trial severance,
    because the codefendant's testimony was "cumulative" of other
    testimony).
    What   is   more,     limiting   instructions   are   usually
    sufficient antidotes to potential prejudice.     See 
    Zafiro, 506 U.S. at 539
    (explaining that even "[w]hen the risk of prejudice is
    high," a judge can take other measures short of severance, like
    offering "limiting instructions," which "often will suffice to
    cure any risk of prejudice"). And here, the judge cautioned jurors
    that counsel's contentions are not evidence.       She also said that
    the government had to prove each defendant's guilt beyond a
    reasonable doubt, and so jurors could not "think of the defendants
    as a group" but had "to give separate consideration to the case
    against each defendant."      Staying with that theme, she later told
    them that they had to "separately consider the evidence against
    each defendant on each count and return a separate verdict with
    respect to each defendant."      That these instructions sufficed to
    dispel any risk of prejudice is confirmed by the fact that they
    essentially mimic those deemed sufficient in Zafiro.
    - 21 -
    The    Zafiro    defendants        had    mutually   antagonistic
    defenses:   Gloria Zafiro said she had no idea that a suitcase Jose
    Martinez (her boyfriend) kept in her apartment had drugs; Martinez
    said he had no idea that Zafiro was involved in selling 
    drugs. 506 U.S. at 536
    .     The defendants sought severance, claiming (among
    other things) that the jury would believe only one defense and so
    would find the other guilty regardless of whether the prosecution
    had proved its case beyond a reasonable doubt.               
    Id. at 540.
        The
    Supreme   Court    found    no   need   for    severance,   noting    that   the
    following instructions cured any possibility of prejudice:                   the
    prosecution had "the burden of proving beyond a reasonable doubt"
    that each defendant committed the charged crimes; the jury had to
    "give separate consideration to each individual defendant and to
    each separate charge against him"; "[e]ach defendant is entitled
    to have his or her case determined from his or her own conduct and
    from the evidence [that] may be applicable to him or her"; and
    opening and closing statements are not evidence.              
    Id. at 541.
    We    presume    that   juries      follow    instructions     about
    potentially prejudicial evidence — until and unless "there is an
    'overwhelming     probability'      that      the    instruction[s]   will    be
    ineffectual." Blake v. Pellegrino, 
    329 F.3d 43
    , 50 (1st Cir. 2003)
    (quoting Richardson v. Marsh, 
    481 U.S. 200
    , 208 (1987)); see also
    - 22 -
    
    Sepulveda, 15 F.3d at 1184
    .            Chisholm has not made any such
    showing, however.
    The bottom line is that the judge's denial of Chisholm's
    mistrial motion based on London's defense strategy survives abuse-
    of-discretion scrutiny.
    SUBSTANTIVE-REASONABLENESS CLAIM
    Background
    Congress established "a three-tiered type-and-quantity-
    driven   sentencing    regime"   for   narcotics-law      violations.     See
    United States v. Eirby, 
    515 F.3d 31
    , 32-33 (1st Cir. 2008).              Take
    heroin, the drug at issue here:             the most severe tier sets a
    minimum term sentence of 10 years and a maximum of life for covered
    offenses   involving     "1   kilogram      or   more,"    see   21     U.S.C.
    § 841(b)(1)(A); the next most severe tier sets a minimum prison
    term of 5 years and a maximum of 40 years for covered offenses
    involving "100 grams or more," see 
    id. § 841(b)(1)(B);
    and the
    least severe tier sets a maximum prison term of 20 years for
    covered offenses involving less than 100 grams (it has no mandatory
    minimum), see 
    id. § 841(b)(1)(C).
           These ranges differ if death or
    serious injury resulted from the drug's use, or if the defendant
    already had a predicate conviction under his belt.                    See 
    id. §§ 841(b)(1)(A)-(C),
    851.
    - 23 -
    As we noted in this opinion's opening paragraph, the
    jury found beyond a reasonable doubt that the amount of heroin
    attributable or reasonably foreseeable to Chisholm was 1 kilogram
    or more.        And as we just said, that amount typically carries a
    minimum penalty of 10 years in prison.            But a prior felony-drug
    conviction of his doubled the minimum to 20 years, as no one
    disputes.6
    At   sentencing,   Chisholm   conceded   responsibility   for
    trafficking 2.227 kilograms of heroin, a number based on the
    controlled buys, the seizures, the intercepted calls, and the
    surveillance.        That number corresponds to a base offense level of
    30.     See USSG § 2D1.1(c)(5) (noting that the base offense level
    for at least 1 kilogram but less than 3 kilograms of heroin is
    30).7       After making arguments not relevant here, Chisholm insisted
    6
    The First Step Act of 2018 changed the minimum from 20 years
    to 15 years. See Pub. L. No. 115-391, § 401, 132 Stat. 5194 (2018)
    (amending 21 U.S.C. § 841(b)(1)(A)(viii)). But because Chisholm
    makes no First Step Act-based arguments, we say nothing else about
    that provision.
    7   For anyone in need of a quick sentencing primer:
    Sentencing under the federal sentencing guidelines
    starts with the base offense level — i.e., a point score
    for a specified offense or group of offenses.        The
    guidelines then make adjustments for any aggravating or
    mitigating factors in the defendant's case, thus
    arriving at a total offense level. The guidelines also
    assign points based on the defendant's criminal history
    — points that get converted into various criminal
    history categories, designated by Roman numerals I
    through VI. Armed with this info, the judge turns to
    - 24 -
    that he had a guidelines sentencing range of 324 months (23 years)
    to 405 months (33.75 years).        And he ultimately asked for the
    mandatory-minimum sentence of 20 years.
    The government, contrastingly, contended that the judge
    had to add to the 2.227-kilogram figure the multiple kilograms
    that the cooperating witnesses had pinned on Chisholm — which,
    when done, would make him responsible for at least 3 kilograms of
    heroin and put him at a base offense level of 32.                 See 
    id. § 2D1.1(c)(4)
    (noting that the base offense level for at least 3
    kilograms but less than 10 kilograms of heroin is 32).                 The
    government also argued that he had a sentencing range of 360 months
    (33 years) to life.    And the government requested a 35-year term.
    Expressing    unease      about   using    any    cooperator's
    uncorroborated   testimony,   the   judge   zeroed   in    on   Chisholm's
    recorded comment to Pelland about selling Serriello a "half a
    brick" a week (a comment mentioned in footnote 5).         And the judge
    the guidelines's sentencing table. And by plotting the
    defendant's total offense level along the table's
    vertical axis and his criminal history category along
    the table's horizontal axis, the judge ends up with an
    advisory prison range. From there, the judge sees if
    any departures are called for, considers various
    sentencing factors, and determines what sentence
    (whether within, above, or below the suggested range)
    seems appropriate.
    United States v. Martínez-Benítez, 
    914 F.3d 1
    , 2 n.2 (1st Cir.
    2019) (citations omitted).
    - 25 -
    found that even if Chisholm had exaggerated a little about sale
    frequency, and even if each sale involved only 200 grams (an amount
    referenced by an agent at sentencing), he "clearly" sold heroin
    "multiple times, and [that] gets [Chisholm] over 3" kilograms.                   So
    the   judge    fixed     his   base   offense   level     at   32,   made   various
    adjustments not pertinent here, set his total offense level at 41,
    and placed him in criminal history category III — which resulted
    in a sentencing range of 360 months to life.                   And after weighing
    the relevant sentencing factors, the judge settled on a term of
    360 months (30 years) — which the judge adjusted downward to 342
    months (28.5 years) to account for the time Chisholm had already
    served on a related state charge.
    Chisholm concedes to us that the judge calculated the
    correct guidelines sentencing range, admitting (as he must) that
    the guidelines let judges aggregate drug quantities for sentencing
    purposes. See USSG § 2D1.1 cmt. n.5 (noting that "[i]f the offense
    involved      both   a   substantive    drug    offense    and    an   attempt    or
    conspiracy (e.g., sale of five grams of heroin and attempt to sell
    an additional ten grams of heroin), the total quantity involved
    shall be aggregated to determine the scale of the offense").                     But
    he insists that the judge should have used her discretion to
    sentence him more in line with the penalty range set out in
    § 841(b)(1)(B) for persons convicted of offenses involving more
    - 26 -
    than 100 grams but less than 1 kilogram of heroin.              And he bases
    his claim on the following multi-step argument:
    A. He   asserts   that    the   controlling      statutes   talk   about       "a
    violation" of the narcotics law — "distribut[ion] . . . or
    possess[ion]    with    intent    to    . . .   distribute      .   .   .   a
    controlled     substance,"       see     21   U.S.C.     §§ 841(b)(1)(A)
    (emphasis added), 841(a)(1) — as well as conspiracy to do the
    same, see 
    id. § 846.
            Pointing to United States v. Zuleta-
    Molina, 
    840 F.2d 157
    (1st Cir. 1988) (per curiam), he contends
    that "[t]he unit of prosecution" for § 841 "is transactional
    — not aggregation based."         So, in his view, the aggregation
    of multiple transactions — each of which he says is a separate
    violation — clashes with the drug laws' plain language.
    B. Then   he   suggests   that   the      statutes'   legislative      history
    indicates that Congress divided traffickers into three tiers,
    from highest to lowest rank:           "manufacturers or the heads of
    organizations"; "managers of the retail[-]level traffic, the
    person[s] . . . filling the bags of heroin . . . and doing so
    in substantial street quantities"; and everyone below the
    retail-level managers.        See H.R. Rep. No. 99-845, pt. 1, at
    12, 17 (1986).    And he intimates that one is a manufacturer
    or head if he deals 1 or more kilograms of heroin, while one
    - 27 -
    is a retail-level manager if he deals "100 grams [to] 1
    kilogram" of heroin.
    C. From there he insists that the government offered "no credible
    evidence" that he participated "in a single transaction of
    one kilogram or more" — thus making him at most "a retail-
    level manager," putting him in the "100 grams [to] 1 kilogram"
    level for punishment purposes, which he says warrants a base
    offense level of 24.            See USSG § 2D1.1(8) (noting that at
    least 100 grams but less than 400 grams of heroin yields a
    base offense level of 24).
    D. And by not using her discretion to impose a sentence that
    jibes    more   with     that     level     —    remember,       she    found    him
    responsible      for    3   kilograms       or     more     of    heroin,    which
    corresponds to a base offense level of 32 — the judge imposed
    an   overly      harsh      sentence,           amounting        to    substantive
    unreasonability (he believes that she should have given him
    20 years, not 30 (reduced to 28.5)).
    The   government,       for   its   part,     defends         the   judge's
    sentencing    decision      to   the    hilt.         Among    other       points,    the
    government argues that the guidelines require aggregation.                           And,
    the government adds, the judge's sentencing discretion clearly
    includes the power to follow them.             More, the government says that
    "[i]t is unclear" how Chisholm's "transaction-based" theory makes
    - 28 -
    the guidelines's "use of aggregated quantities infirm" in the
    conspiracy context.     The government also stresses that Chisholm
    "regularly    distributed    large   quantities   of   a   deadly   drug,"
    obviously aware "of its dangers."      So the government asserts that
    the sentence was not unjustifiably severe.
    Standard of Review
    A sentence is substantively unreasonable "only if it
    falls beyond the expansive 'universe of reasonable sentencing
    outcomes.'"    United States v. Rodríguez-Torres, No. 16-1507, 
    2019 WL 4463275
    , at *20 (1st Cir. Sept. 18, 2019) (quoting United States
    v. Bermúdez-Meléndez, 
    827 F.3d 160
    , 167 (1st Cir. 2016)).           And we
    review the substantive reasonableness of the judge's sentence for
    abuse of discretion, knowing that a sentence must stand if she
    gave a plausible explanation and reached a defensible result. See,
    e.g., United States v. Tanco-Pizarro, 
    892 F.3d 472
    , 483-84 (1st
    Cir. 2018).
    Analysis
    We find several problems with Chisholm's argument.        For
    openers, his step-A complaint about aggregation rings hollow,
    given how he conceded at sentencing to having distributed 2.227
    kilograms of heroin — a number that could only be reached through
    aggregation.     And unfortunately for him, the Federal Reporter is
    full of our opinions saying that "[a]n appellant cannot change
    - 29 -
    horses    in    mid-stream,   arguing   one   theory   below   and   a   quite
    different theory on appeal."8       See Ahern v. Shinseki, 
    629 F.3d 49
    ,
    58 (1st Cir. 2010).
    This concern aside, Chisholm's argument also rests on a
    mistake about conspiracy law.           A conspiracy is an agreement to
    commit some other crime, see United States v. Shabani, 
    513 U.S. 10
    , 16 (1994) — though it "may, and often does, encompass an array
    of substantive illegal acts carried out in furtherance of the
    overall scheme," see United States v. Pressley, 
    469 F.3d 63
    , 65
    (2d Cir. 2006) (per curiam) (citing United States v. Broce, 
    488 U.S. 563
    , 570-71 (1989), and Braverman v. United States, 
    317 U.S. 49
    , 53-54 (1942)).       And for a drug conspiracy — the essence of
    which is an agreement to violate the narcotics laws — "these
    subsidiary crimes may take the form of a series of smaller drug
    sales."    See 
    Pressley, 469 F.3d at 65
    .
    So because "[a] conspiracy . . . is a single offense,"
    see United States v. Manjarrez, 
    306 F.3d 1175
    , 1181 (1st Cir.
    2002), it "constitutes 'a violation'" for § 841(b) purposes, see
    
    Pressley, 469 F.3d at 66
    (quoted language taken from the statute).
    And in sentencing a narcotics-conspiracy member under § 841(b),
    8 While we are on the topic of changing horses, Chisholm
    pushed for a base offense level of 30 in the district court but
    now suggests that level should be 24 — an effort that also runs
    headlong into Ahern.
    - 30 -
    the offense involves the aggregate of all drugs "attributable to[]
    or reasonably foreseeable by" him.            See United States v. Walker-
    Couvertier, 
    860 F.3d 1
    , 17 (1st Cir. 2017) (quoting United States
    v. Cintrón-Echautegui, 
    604 F.3d 1
    , 5 (1st Cir. 2010)); see also
    United States v. Dunston, 
    851 F.3d 91
    , 100 (1st Cir. 2017);
    
    Pressley, 469 F.3d at 66
    .
    Nor does Zuleta-Molina save his "transactional — not
    aggregation based" theory.       True, that case held that § 841's
    "language . . . unequivocally indicates that the government may
    prosecute each individual act of distribution."             
    See 840 F.2d at 158
    .   But    the   indictment   there    charged     the   defendant   with
    substantive § 841 offenses, not conspiracy.           See 
    id. at 157.
        And
    "[g]iven the conceptional distinction between conspiratorial and
    substantive   liability,"   nothing      in    Zuleta-Molina   reflects    an
    attempt "to insulate drug conspirators from the long-standing rule
    treating a conspiracy as a single, unified violation."                    See
    
    Pressley, 469 F.3d at 66
    .
    As for Chisholm's step-B attempt to seek refuge in
    legislative history — recall his talking about "manufacturers or
    heads of organizations"; "managers of the retail[-]level traffic;"
    etc. — we note that even for those who find legislative history
    relevant, the history he plays up is anything but.              This is so
    because we are not faced with unclear statutory language.               See,
    - 31 -
    e.g., Milner v. Dep't of the Navy, 
    562 U.S. 562
    , 574 (2011)
    (explaining that "[l]egislative history, for those who take it
    into account, is meant to clear up ambiguity, not create it");
    United States v. Gonzales, 
    520 U.S. 1
    , 6 (1997) (declaring that
    where statutory language is plain, "there is no reason to resort
    to legislative history"); Gemsco, Inc. v. Walling, 
    324 U.S. 244
    ,
    260 (1945) (holding that "[t]he plain words and meaning of a
    statute cannot be overcome by a legislative history which, through
    strained processes of deduction from events of wholly ambiguous
    significance, may furnish dubious bases for inference in every
    direction").     And this is also so because, for reasons just given,
    applying   the   statutory   language   produces   no   patently   absurd
    result.    See, e.g., INS v. Cardoza-Fonseca, 
    480 U.S. 421
    , 452
    (1987) (Scalia, J., concurring) (emphasizing that "if the language
    of a statute is clear, that language must be given effect . . . at
    least in the absence of a patent absurdity").
    If more were needed — and it isn't — Chisholm's step-B
    and step-C thoughts about how he should be viewed more like a
    retail-level manager for sentencing purposes are not difference-
    makers either.      He dug that label out of legislative history,
    recall, as he did the manufacturer-or-head-of-organization label;
    neither label appears in 21 U.S.C. § 841(b) or in USSG § 2D1.1(c)
    — which rely on drug quantities, not malleable titles.             And we
    - 32 -
    just explained why we need not resort to legislative history.   But
    even if the labels mattered for our analysis, and even if a retail-
    level manger corresponded to the "100 grams [to] 1 kilogram tier"
    (a claim he makes without pointing to controlling authority), he
    would still lose, because his taking responsibility for 2.227
    kilograms of heroin blows a huge hole in his theory.
    The net result is nothing Chisholm says convinces us
    that his sentence is implausible or indefensible.      And by not
    offering us a persuasive basis to override the judge's exercise of
    her discretion, he gets no sentencing do-over.
    ENDING
    Having worked our way through Chisholm's issues, we
    affirm the challenged convictions and sentence.
    - 33 -