United States v. Samuel Navarrette-Aguilar , 813 F.3d 785 ( 2015 )


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  •                 FOR PUBLICATION
    UNITED STATES COURT OF APPEALS
    FOR THE NINTH CIRCUIT
    UNITED STATES OF AMERICA,                No. 14-30056
    Plaintiff-Appellee,
    D.C. No.
    v.                       3:12-cr-00373-
    HZ-1
    SAMUEL NAVARRETTE-AGUILAR,
    AKA Guayabo,
    Defendant-Appellant.          OPINION
    Appeal from the United States District Court
    for the District of Oregon
    Marco A. Hernandez, District Judge, Presiding
    Argued and Submitted
    March 3, 2015—Portland, Oregon
    Filed December 28, 2015
    Before: Raymond C. Fisher, Richard A. Paez,
    and Sandra S. Ikuta, Circuit Judges.
    Opinion by Judge Paez
    2         UNITED STATES V. NAVARRETTE-AGUILAR
    SUMMARY*
    Criminal Law
    The panel affirmed in part, reversed in part, and vacated
    in part a criminal judgment in a case in which a jury
    (1) found the defendant guilty of conspiracy to distribute
    heroin, distribution of heroin, and possession of heroin with
    intent to distribute; and (2) made a special finding that the
    quantity of heroin was at least one kilogram, triggering a
    mandatory minimum twenty-year sentence under 21 U.S.C.
    § 841(b)(1)(A)(i).
    The panel concluded, as did the district court, that the
    testimonial and physical evidence cannot support a finding of
    one kilogram. The panel held that the district court erred,
    however, in determining that the pattern of transactions
    permitted the jury to conclude that members of the conspiracy
    would have eventually distributed one kilogram of heroin.
    The panel wrote that it would be speculative to infer that the
    defendants agreed to any future transactions such that they
    would reach the one kilogram mark. The panel held that the
    error was not harmless, and therefore reversed the jury’s
    quantity finding, vacated the sentence on all counts, and
    remanded for re-sentencing.
    Affirming the convictions, the panel held that the district
    court did not abuse its discretion when it permitted the
    government to ask the defendant’s sister, a defense witness,
    about the defendant’s prior convictions, where the witness
    *
    This summary constitutes no part of the opinion of the court. It has
    been prepared by court staff for the convenience of the reader.
    UNITED STATES V. NAVARRETTE-AGUILAR                    3
    opened the door to impeachment. The panel concluded that
    even if the district court did abuse its discretion, the error was
    harmless.
    COUNSEL
    Per C. Olson (argued), Hoevet Boise Olson Howes, Portland,
    Oregon, for Defendant-Appellant.
    Kelly A. Zusman (argued), Appellate Chief, Assistant United
    States Attorney and S. Amanda Marshall, United States
    Attorney for the District of Oregon, Portland, Oregon, for
    Plaintiff-Appellee.
    OPINION
    PAEZ, Circuit Judge:
    Samuel Navarrette-Aguilar (“Navarrette”) appeals his
    conviction and sentence. A jury found him guilty of
    conspiracy to distribute heroin, distribution of heroin,
    possession of heroin with intent to distribute, and made a
    special finding that the quantity of heroin was at least one
    kilogram. Navarrette argues that substantial evidence did not
    support the jury’s quantity finding. The evidence of historical
    transactions adduced did not amount to one kilogram.
    Navarrette maintains that when the district court denied his
    motions for judgment of acquittal, it erred in determining that
    the pattern of transactions permitted the jury to conclude that
    members of the conspiracy would have eventually distributed
    one kilogram of heroin. Navarrette further argues that the
    district court abused its discretion when it permitted the
    4       UNITED STATES V. NAVARRETTE-AGUILAR
    government to ask a defense witness on cross-examination
    about his prior convictions for drug trafficking and escape.
    Although we affirm Navarrette’s convictions on the
    conspiracy and distribution counts, we reverse the district
    court’s ruling on the jury’s quantity finding, vacate his
    sentence, and remand for re-sentencing.
    I.
    Navarrette was charged with Conspiracy to Traffic Heroin
    in a quantity of one kilogram or more; Distribution of Heroin
    Resulting in Death; and Possession with Intent to Distribute
    Heroin. 21 U.S.C. §§ 841, 846. He was also charged with
    the penalty provision for distributing a kilogram or more of
    heroin, 21 U.S.C. § 841(b)(1)(A)(i), which provides for a
    mandatory minimum twenty-year sentence for a defendant
    who, like Navarrette, has a prior felony drug conviction. The
    government also charged him with the penalty provision for
    distributing a schedule I controlled substance resulting in
    death or serious injury, 21 U.S.C. § 841(b)(1)(C). The
    government charged two co-defendants along with
    Navarrette: Saul Guzman-Arias, who proceeded to trial with
    Navarrette, and Antonio Equihua-Ramirez, who pled guilty
    and became a witness for the prosecution.
    A jury trial commenced on June 4, 2013. Because this
    appeal turns on whether there was substantial evidence to
    support the jury’s finding that Navarrette and his co-
    defendants conspired to distribute at least one kilogram of
    heroin, we discuss the evidence produced at trial in detail.
    UNITED STATES V. NAVARRETTE-AGUILAR                       5
    The government investigated and prosecuted Navarrette
    as a “Len Bias”1 case—that is, they sought to prove a supply
    chain directly linking the top of the chain, Navarrette, to the
    heroin overdose death of a woman named Erin Freeman.
    Distribution of a schedule I or II narcotic resulting in a death
    or serious injury carries a twenty-year mandatory minimum
    sentence, and a mandatory life sentence for those with a prior
    felony drug conviction. 21 U.S.C. § 841(b)(1)(C). Seeking
    this heavy penalty, the government sought to prove the
    connections among the members of the supply chain. As the
    evidence at trial showed, the investigation proceeded by using
    information from lower-level dealers to pursue higher-level
    distributors.
    The government presented the jury with a narrative of the
    investigation process through the testimony of several
    officers, including Portland Police Officer Tim Manzella.
    Officer Manzella testified that, with the assistance of
    Freeman’s boyfriend, he set up a controlled purchase of
    heroin from her immediate supplier, Bruce McDaniel. While
    watching McDaniel’s house, Officer Manzella saw Josef
    Burns arrive; after he left, Manzella conducted a traffic stop
    1
    Many of the provisions of 21 U.S.C. § 841, including
    the twenty-year minimum prison term for causing a
    heroin overdose death, are often referred to as the Len
    Bias laws after a popular college basketball star. Len
    Bias played basketball for the University of Maryland
    until a drug overdose caused his untimely death in
    1986. Congress enacted the provisions of 21 U.S.C.
    § 841 under the theory that but for their purchase of
    drugs the overdose victims would not have died.
    Katherine Daniels & Carol M. Bast, Difficulties in Investigating and
    Prosecuting Heroin Overdose Cases, 41 Crim. L. Bull. 513, 517 (2005).
    6         UNITED STATES V. NAVARRETTE-AGUILAR
    of Burns. During their encounter, Burns admitted that he was
    McDaniel’s heroin supplier.         Officer Manzella then
    engineered another controlled purchase of heroin using
    Burns, which led local law enforcement officers to the next
    supplier up the chain, Antonio Equihua-Ramirez. Equihua-
    Ramirez was arrested at the buy location, and officers found
    sixty-two grams of heroin and between $7,600 and $7,800 in
    cash in his vehicle. Equihua-Ramirez agreed to cooperate
    with the police and consented to a search of his home, where
    police found approximately thirteen grams2 of heroin. Officer
    Manzella testified that Equihua-Ramirez had told him that the
    cash in his car was the profits from his sale of 150 grams of
    heroin, which he planned to turn over to his supplier, who had
    “fronted” him the drugs. Additionally, upon seizing Equihua-
    Ramirez’s phone, Officer Manzella found a text message,
    sent to a number later determined to be Navarrette’s, in which
    Equihua-Ramirez attempted to place an order for eight more
    pieces of heroin (200 grams) once he finished selling what he
    had.
    Using Equihua-Ramirez, officers set up another
    controlled buy, this time from Equihua-Ramirez’s supplier,
    whom he knew as “Califas,” for the 200 grams that Equihua-
    Ramirez had already attempted to order. Officers arrested
    Saul Guzman-Arias, who appeared at the appointed time.
    Equihua-Ramirez identified him as the go-between who
    delivered the drugs that Equihua-Ramirez ordered from
    “Califas.” Officers searched Guzman-Arias’s car and
    2
    Throughout their testimony, witnesses used different measurements –
    ounces, pieces, and grams – to describe the quantities of their transactions.
    An ounce is approximately twenty-eight grams; a “piece” is approximately
    twenty-five grams. We have converted all measurements to grams using
    this scale.
    UNITED STATES V. NAVARRETTE-AGUILAR                  7
    recovered 199.03 grams of heroin (the eight piece order) from
    a hidden compartment, capable of holding up to forty pounds
    of contraband, in his car. The police officers obtained cell
    site information relating to the phone Equihua-Ramirez used
    to place orders for heroin and used GPS to find the location
    of the phone he called, belonging to “Califas.” Police
    arrested “Califas,” revealed to be Navarrette, at his home.
    They did not find any drugs, but they did recover $1,860 in
    cash, and also discovered a large hidden compartment in his
    vehicle that could have held up to thirty pounds of
    contraband. Thus, the total amount of heroin recovered and
    presented as physical evidence at trial was approximately 274
    grams.
    In addition to the physical evidence, the government
    presented several defendants’ phone records, as well as a few
    wiretapped calls from a federal investigation that had also
    ensnared Guzman-Arias, but none of these yielded evidence
    of the specific quantity of heroin transacted. Instead, the
    phone records presented, which included the records of
    Equihua-Ramirez, Navarrette, and Guzman-Arias, showed the
    number and frequency of calls and text messages among
    several members of the conspiracy. Local law enforcement
    officers also testified that they used a call placed from
    Equihua-Ramirez to Navarrette to triangulate the location of
    Navarrette, in order to arrest him, as evidence of Navarrette’s
    identity as “Califas.” As none of these other pieces of
    evidence would permit the jury to find that the conspiracy
    involved at least a kilogram of heroin, the government’s main
    evidence of quantity came from the testimony of Equihua-
    Ramirez and Burns.
    Burns testified that, during the time period alleged
    (approximately two and a half months, from mid-March to
    8       UNITED STATES V. NAVARRETTE-AGUILAR
    early June), he only purchased heroin from Equihua-Ramirez,
    and Equihua-Ramirez testified that he only purchased heroin
    from Navarrette. Equihua-Ramirez further testified that
    Burns was his biggest customer, and his “[a]bout five” other
    customers only bought about a gram of heroin at a time,
    without specifying in greater detail how much heroin they
    purchased. Therefore, the government had to prove an
    agreement to distribute a kilogram of heroin from either
    a) Equihua-Ramirez’s testimony as to how frequently he
    purchased heroin from Navarrette; b) Equihua-Ramirez’s
    testimony as to how frequently he sold heroin to Burns; or
    c) Burns’s testimony as to how frequently he purchased
    heroin from Equihua-Ramirez.
    A. Testimony of Josef Burns
    Josef Burns could not state with certainty how many
    times and in what quantities he had purchased heroin from
    Equihua-Ramirez. For example, Burns initially stated that he
    had purchased heroin “more than a dozen times,” but later
    said that he “[did]n’t know [how many times].” When
    pressed on cross-examination, he agreed that a more realistic
    range was twelve to sixteen transactions, and stated “I mean,
    whatever. I mean, I’m not sure. I can’t exactly say.” On
    cross-examination, Burns also waffled on how long he had
    been buying from Equihua-Ramirez:
    Q. Yeah. Is it possible your relationship
    started sometime in late April?
    A. In April?
    Q. Correct. So it would have been about a
    month and a half?
    UNITED STATES V. NAVARRETTE-AGUILAR                 9
    A. March, April, something like that. April,
    May, June, yeah, something around there.
    Q. You don’t really have a definite memory of
    that?
    A. I don’t have a definite—I don’t have a
    definite time on that.
    Describing his purchasing practices, Burns stated that he
    began by buying “one piece [twenty-five grams] and then two
    or three.” He testified that he could not estimate the total
    amount of heroin that he purchased, but that it took him “a
    month or two” to “wor[k] up to two or three pieces.” We
    note again that the entire time period of the conspiracy
    alleged was approximately two and a half months. When
    questioned about the frequency with which he purchased
    heroin, Burns stated that it could be one or two times a week,
    but also “maybe a few more times . . . maybe three or four
    max.” He went on to explain that the frequency with which
    he purchased and the amount he purchased “would all just
    depend” on the level of demand, which was “different all the
    time.” The variation in the amount Burns purchased is borne
    out by other record evidence. Notably, on May 26, Burns
    received a text message from Equihua-Ramirez asking him
    why he was not purchasing more heroin. When presented
    with this evidence, Burns responded
    Yeah. I think I just—I just hadn’t called them
    in a little bit or whatever. I was not very—I
    didn’t really want to sell heroin. I did it
    because I didn’t know what else to do, really.
    I couldn’t do what I used to do, any of the
    10       UNITED STATES V. NAVARRETTE-AGUILAR
    jobs I used to do. But I didn’t want to do it.
    I just did it because—I don’t know.
    Burns testified several times that he had difficulty
    remembering details of the time period in question. For
    example, when questioned more specifically about his
    practice of selling heroin, Burns answered, “I’m trying to
    think. I’m not prepared for all this. I can’t really remember.”
    And, later, Burns stated in response to further questioning:
    “I’m not really on it. . . . I just had a lot going on in the last
    year since this happened so I haven’t been dealing with any
    of this.”
    In sum, Burns’s testimony was vague; he could not
    provide an estimate as to how much heroin he sold or
    purchased, and could not clearly remember or describe his
    practices during the time in question.
    B. Testimony of Antonio Equihua-Ramirez
    Like Burns, Equihua-Ramirez gave equivocal testimony
    regarding the frequency with which he bought and sold
    heroin. Officer Manzella’s testimony revealed that, before
    trial, Equihua-Ramirez contradicted himself in his statements
    to the police. For example, he initially told Officer Manzella
    that he had been dealing for a period of six months, but later
    stated that he had only been dealing since mid-March. It
    “seemed to [Officer Manzella] that he was pretty confused
    about the exact start and end date.” Equihua-Ramirez also
    gave different statements to police at different times
    regarding the amount that he sold to Burns.
    At trial, Equihua-Ramirez testified that he began selling
    heroin in March of 2012, upon taking over the business of a
    UNITED STATES V. NAVARRETTE-AGUILAR                11
    friend of his while that friend returned to Mexico. It was to
    be a temporary arrangement. Equihua-Ramirez only bought
    drugs from “Califas,” the name by which he knew Navarrette.
    Navarrette “fronted” him the drugs, meaning that Equihua-
    Ramirez only paid for the drugs after he sold them to others,
    and did not order more until he had sold all of the drugs that
    he had previously bought. It also meant that he did not buy
    more than he thought he could sell.
    Equihua-Ramirez testified that he began by ordering an
    ounce (twenty-eight grams) at a time, which would take him
    about three days to sell. Equihua-Ramirez further testified
    that he purchased drugs “thirteen or fourteen” times.
    Equihua-Ramirez later testified that he purchased heroin from
    his supplier “between ten and thirteen [times],” but that he
    “[did]n’t remember well.” He maintained that it could not
    have been fewer than ten times.
    Equihua-Ramirez testified that, while he did not always
    purchase a single ounce (28 grams), the most that he ever
    purchased at a single time was four ounces (112 grams),
    which he did shortly before he was arrested. However, his
    last order had been for 200 grams; this would have been his
    largest order.
    Equihua-Ramirez testified that Josef Burns was his
    biggest customer, and that the last sale that he made to Burns
    was for fifty grams. He further stated that Burns usually
    purchased “sometimes one, sometimes two” pieces at a time
    (twenty-five to fifty grams), and once purchased three pieces
    (seventy-five grams). At one point, Equihua-Ramirez
    testified that there was a period in April during which the
    heroin was bad, and his customers stopped buying from him;
    he stated that, as a result, he sold heroin only once in the
    12       UNITED STATES V. NAVARRETTE-AGUILAR
    month of April. He further testified that the poor quality of
    the heroin angered him, and that he wanted to quit as a result.
    He later testified, however, that the period in which Burns
    refused to buy from him was approximately fifteen days, that
    Burns then bought an ounce (twenty-eight grams) from him
    in order to test the quality, and that he did not recall when that
    purchase had taken place.
    Like Burns, Equihua-Ramirez did not concretely or
    consistently testify as to the number of transactions or their
    amount, and no clearer pattern of sales emerges from his
    testimony than from Burns’s.
    C. The District Court’s Ruling and Order
    The jury found Navarrette and Guzman-Arias guilty of
    the Conspiracy, Distribution of Heroin, and Possession
    charges, but did not find true that the distribution of heroin
    resulted in the death of another. The jury, however, found
    true that Navarrette conspired to distribute a kilogram or
    more of heroin. After the verdict, Guzman-Arias renewed his
    motion for judgment of acquittal under Rule 29 of the Federal
    Rules of Criminal Procedure, arguing that the evidence was
    insufficient as a matter of law to establish that the conspiracy
    involved a quantity of at least one kilogram of heroin;
    Navarrette joined in the motion, which the court denied in a
    written order.
    The court first summarized the evidence discussed above.
    Noting that the testimony of both Burns and Equihua-
    Ramirez was vague and failed to specify the total quantity of
    heroin that either purchased, and applying the substantial
    evidence standard from United States v. Nevils, 
    598 F.3d 1158
    (9th Cir. 2010) (en banc), the court employed two
    UNITED STATES V. NAVARRETTE-AGUILAR                       13
    different approaches to determine the amount of heroin that
    the jury could have found without speculation.
    First, the court analyzed the amount of heroin the jury
    could have inferred from Equihua-Ramirez’s testimony as to
    the number of purchases he made from Navarrette through
    Guzman-Arias. Construing the evidence in the light most
    favorable to the prosecution, 
    id. at 1161,
    the court concluded
    that the jury could have found that Equihua-Ramirez
    purchased heroin fourteen times, and that the last purchase
    was for 100 grams.3 Adding the 274 grams that both
    defendants conceded were attributable to the conspiracy (the
    75 grams found in the two searches of Equihua-Ramirez’s
    property, and the 199 grams found in Guzman-Arias’s car),
    the court reached a total of 374 grams. However, the court
    concluded that for the remaining thirteen purchases, the jury
    could only speculate as to how many times Equihua-Ramirez
    purchased one, two, or three ounces. Therefore, the court
    concluded that the only amount that the jury could have found
    without engaging in speculation was the least of these, as it
    was certain that Equihua-Ramirez purchased at least one
    ounce in each of the thirteen transactions. Thus, taking
    Equihua-Ramirez’s testimony and physical evidence alone,
    the court concluded that the jury could have found beyond a
    reasonable doubt that the conspiracy involved 699 grams of
    3
    It is unclear whether the district court meant pieces (25 grams) or
    ounces; four ounces would be 112 grams, whereas four pieces would be
    100.
    14        UNITED STATES V. NAVARRETTE-AGUILAR
    heroin (274 grams found, plus 100 grams admitted as the last
    purchase, plus 325 grams).4
    Next, the court analyzed Burns’s testimony to determine
    the quantity of heroin that the jury could have inferred
    without speculation. Noting again the inconsistencies in
    Burns’s testimony with regard to the frequency with which he
    purchased heroin, the court turned to the phone records
    showing calls between Equihua-Ramirez and Burns in order
    to estimate the number of transactions between them. While
    the court arrived at a number of transactions it believed was
    adequately supported by the phone records and testimony, the
    court observed that, again, the jury would have had to
    speculate as to how much heroin was involved in each.
    Nonetheless, the court concluded that the jury could have
    found without speculation that Burns purchased 750 grams
    from Equihua-Ramirez, based on Burns’s testimony that he
    purchased “a few,” or three pieces (75 grams) per week, and
    based on the assumption of a ten-week period.
    Thus, the court found that the physical and testimonial
    evidence did not reach the one kilogram quantity threshold.
    The court concluded, however, that Equihua-Ramirez’s and
    Burns’s testimony provided the jury
    a reasonable ‘guide’ as to the total amount
    that was involved in the conspiracy. Based on
    the history of dealing from mid-March to
    4
    It is again unclear whether the court meant “pieces” or ounces in
    coming to the total of 325 grams; 28 grams per ounce multiplied 13 times
    is actually 364 grams, which would bring the total to 750 grams – 274
    grams found, plus 112 grams (four ounces) for the last purchase, plus 13
    purchases totaling 364 grams.
    UNITED STATES V. NAVARRETTE-AGUILAR                 15
    early June 2012 . . . and construing the
    evidence and inferences in the Government’s
    favor, the jury could have made a reasonable,
    non-speculative inference that Defendants
    must have agreed to distribute as much heroin
    as they could and that the distribution would
    have continued in a similar fashion.
    That is, the court concluded that the evidence in the record
    established a pattern of transactions that would have allowed
    the jury to infer a preexisting agreement to distribute at least
    a kilogram of heroin.
    Count One carried a mandatory minimum of twenty
    years, due to Navarrette’s prior conviction and the jury’s
    special finding. Count Two carried no mandatory minimum,
    and Count Four carried a mandatory minimum of ten years.
    On the basis of the jury’s quantity finding, as well as an
    increase of three levels for Navarrette’s role in the
    conspiracy, and after subtracting two levels for an anticipated
    change in the U.S. Sentencing Guidelines, the court
    calculated a base offense level of thirty-three. After
    considering Navarrette’s criminal history, the court calculated
    the guideline range for each count as 168–210 months, before
    taking into account the mandatory minimum on Count One.
    The court then sentenced Navarrette to 240 months on each
    count of conviction (the mandatory minimum on Count One
    due to the the one kilogram quantity), to run concurrently,
    and to a 10-year term of supervised release following his
    incarceration. The court used the same base offense level in
    imposing the sentences on each count.
    16       UNITED STATES V. NAVARRETTE-AGUILAR
    II.
    A. Standard of Review and Jurisdiction
    Both with respect to his sentence and his conviction,
    Navarrette appeals a final judgment of a district court, and
    thus we have jurisdiction under 28 U.S.C. § 1291.
    Navarrette first challenges the jury’s quantity finding for
    the conspiracy to distribute and distribution charges. He does
    not raise an evidence insufficiency challenge to the jury’s
    verdict with respect to his convictions for any of the
    substantive offenses. After Apprendi v. New Jersey, 
    530 U.S. 466
    (2000), “[w]e . . . trea[t] drug quantity and type, which
    fix the maximum sentence for a conviction, as we would any
    other material fact in a criminal prosecution: it must be
    charged in the indictment, submitted to the jury, subject to the
    rules of evidence, and proved beyond a reasonable doubt.”
    United States v. Buckland, 
    289 F.3d 558
    , 568 (9th Cir. 2002);
    see also United States v. Vera, 
    770 F.3d 1232
    (9th Cir. 2014).
    The jury’s quantity finding subjected Navarrette to a twenty-
    year mandatory minimum sentence, as he had previously
    been convicted of a drug felony, 21 U.S.C. § 841(b)(1)(A)(i);
    setting aside this finding would mean that he is no longer
    subject to that mandatory minimum. Thus, the jury had to
    find the one kilogram quantity beyond a reasonable doubt.
    We review a jury’s verdict and special findings for
    substantial evidence, which requires that we first “construe
    the evidence ‘in the light most favorable to the prosecution,’
    and only then determine whether ‘any rational trier of fact
    could have found the essential elements of the crime beyond
    a reasonable doubt.’” 
    Nevils, 598 F.3d at 1161
    (quoting
    
    Jackson, 443 U.S. at 319
    ). This means that “when faced with
    UNITED STATES V. NAVARRETTE-AGUILAR                  17
    a record of historical facts that supports conflicting inferences
    [we] must presume . . . that the trier of fact resolved any such
    conflicts in favor of the prosecution, and must defer to that
    resolution.” 
    Id. at 1164
    (internal quotation marks omitted).
    However, “[a]lthough we must draw all reasonable inferences
    in favor of the prosecution, a ‘reasonable’ inference is one
    that is supported by a chain of logic, rather than . . . mere
    speculation dressed up in the guise of evidence.” Juan H. v.
    Allen, 
    408 F.3d 1262
    , 1277 (9th Cir. 2005).
    Second, Navarrette challenges the district court’s
    admission of evidence of his prior convictions as
    impeachment evidence following the testimony of his sister,
    Mini Navarrette. We review a district court’s evidentiary
    rulings for abuse of discretion. United States v. Castillo,
    
    181 F.3d 1129
    , 1132 (9th Cir. 1999).
    B. Conspiracy Generally
    “To establish a drug conspiracy, the government must
    prove: 1) an agreement to accomplish an illegal objective;
    and 2) the intent to commit the underlying offense.” United
    States v. Mincoff, 
    574 F.3d 1186
    , 1192 (9th Cir. 2009)
    (quoting United States v. Barragan, 
    263 F.3d 919
    , 922 (9th
    Cir. 2001)). The government “can prove the existence of a
    conspiracy through circumstantial evidence that defendants
    acted together in pursuit of a common illegal goal.” United
    States v. Bishop, 
    1 F.3d 910
    , 911 (9th Cir. 1993) (citation
    omitted). “Express agreement is not required; rather,
    agreement may be inferred from conduct.” United States v.
    Hegwood, 
    977 F.2d 492
    , 497 (9th Cir. 1992) (citation
    omitted). Thus, evidence of past transactions can constitute
    circumstantial evidence of a preexisting agreement, because
    18       UNITED STATES V. NAVARRETTE-AGUILAR
    it can be inferred that the defendants agreed to carry out those
    transactions.
    Circumstantial evidence of a drug distribution conspiracy
    is not limited to evidence of past completed transactions.
    See, e.g., United States v. Rosales, 
    516 F.3d 749
    , 755 (9th
    Cir. 2008) (considering evidence of a hydraulic press and
    metal molds that could be used to produce kilogram bricks of
    cocaine in determining that sufficient evidence supported a
    conviction of conspiracy to distribute at least 500 grams of
    cocaine). Moreover, a conspiracy conviction does not require
    “the delivery, presence, or even existence of actual
    contraband.” United States v. Macias-Valencia, 
    510 F.3d 1012
    , 1016 (9th Cir. 2007). But in order for the defendant to
    be subject to a mandatory minimum under § 841(b)(1)(A)(i),
    the government still must prove, beyond a reasonable doubt,
    that an agreement to distribute one kilogram existed before
    the expiration of the period alleged in the indictment. As we
    explain below, the government failed to meet its burden of
    proof.
    C. Physical and Testimonial Evidence Presented
    Before examining whether the circumstantial evidence of
    the defendants’ pattern of transactions can support the one
    kilogram quantity finding, we first consider whether the
    government otherwise presented sufficient evidence to
    establish that amount.
    The government contends that the district court’s finding
    of 750 grams, inferred from Burns’s testimony, plus the 274
    grams conceded by Navarrette, exceeds one kilogram, and
    thus the jury’s finding is supported by substantial evidence.
    Navarrette, in turn, argues that even if the district court failed
    UNITED STATES V. NAVARRETTE-AGUILAR                 19
    to add all of the 274 grams of physical evidence in reaching
    the 750 gram estimate, “it is fair to assume that [the district
    court] counted at least the 62 grams seized from Equihua-
    Ramirez, as this amount was earmarked for Burns.” Even
    adding the remaining 212 grams to the 750 grams inferred
    from Burns’s testimony, the quantity still falls short of one
    kilogram. Navarrette further argues that the district court
    erred when it determined that the conspiracy continued for
    ten weeks, because it was “undisputed that the heroin went
    ‘bad’ for a while during which time Burns purchased heroin
    from Equihua-Ramirez only once,” and, moreover, “Equihua-
    Ramirez testified that this was a substantial period during
    April and May.”
    While it is true that Equihua-Ramirez testified at one
    point that the period during which the heroin went bad lasted
    most of April, at another point during the trial, he testified
    that it lasted approximately fifteen days. Burns likewise
    testified that he did not purchase heroin from Equihua-
    Ramirez for a period, although he did not testify how long
    that lasted. Because we must resolve all conflicting evidence
    in favor of the prosecution, we will use the lower of Equihua-
    Ramirez’s estimates (that is, fifteen days), and conclude that
    the period in which Equihua-Ramirez and Burns conducted
    their transactions spanned eight weeks, not ten (ten weeks
    minus fifteen days). Using the district court’s 75 gram per
    week calculation (from Burns’s testimony that he purchased
    “a few” each week) the total would thus come to 600 grams.
    Even adding 75 grams for the single instance in which Burns
    purchased three pieces, and all of the 274 grams that
    Navarrette conceded, the total amount of heroin established
    would come to 949 grams. There was no evidence presented
    that Equihua-Ramirez’s additional gram-level customers
    would make up the difference.
    20      UNITED STATES V. NAVARRETTE-AGUILAR
    Turning to Equihua-Ramirez’s testimony, even if we
    attempted to determine the quantity of heroin from his
    testimony regarding his sales to Burns (instead of the 699
    grams based on the number of Equihua-Ramirez’s purchases),
    it still would not reach a kilogram. Equihua-Ramirez testified
    that Burns bought “sometimes two, sometimes three” pieces
    a week from him (fifty or seventy-five grams), but also
    testified that Burns stopped buying from him for a period.
    Equihua-Ramirez also testified repeatedly that he only sold
    Burns three pieces on one single occasion. Thus, a relatively
    liberal calculation based on his sales to Burns, as well as his
    admitted four-ounce buy (which risks double-counting, since
    some of that could have been sold to Burns) and the 200
    grams found on Guzman-Arias (his last order) would still not
    total a kilogram: 50 grams multiplied by 8 weeks (two pieces
    per week, and not counting the period the heroin went bad)
    plus 75 grams (the single three piece buy) plus 112 grams
    (the four ounce order) plus 200 grams (the final controlled
    buy) totals 787 grams.
    The district court did not attempt to determine an average
    amount of heroin distributed either from Burns’s testimony or
    from Equihua-Ramirez’s testimony, instead relying on the
    least amount that either defendant testified was his minimum
    sale or purchase. We have previously approved the
    “multiplier method,” for approximating drug quantity “by
    determining a daily or weekly quantity, selecting a time
    period over which it is more likely than not that the defendant
    was dealing in that quantity and multiplying these two factors
    together,” United States v. Culps, 
    300 F.3d 1069
    , 1077 (9th
    Cir. 2002). However, we have done so only in the sentencing
    context, in which the government was required to prove
    quantity by a preponderance of the evidence for sentencing
    purposes, and not, as here, where the factual issue had to be
    UNITED STATES V. NAVARRETTE-AGUILAR                        21
    proved beyond a reasonable doubt. Under the Jackson
    standard, we are obliged to construe the evidence of drug
    quantity adduced at trial “in the light most favorable to the
    prosecution,” and only after viewing the evidence in this
    light, determine whether, resolving all conflicting inferences
    in favor of the prosecution, “any rational trier of fact could
    have found” the one kilogram quantity “beyond a reasonable
    
    doubt.” 443 U.S. at 319
    . Jackson v. 
    Virginia, 443 U.S. at 319
    . Applying the Jackson standard, we conclude that the
    district court did not err in declining to apply the multiplier
    method given the facts of this case.
    We further conclude that the district court did not err in
    disregarding the circumstantial evidence of the secret storage
    compartment in Navarrette’s vehicle, capable of holding 30
    pounds of drugs. The government offered no evidence that
    the storage compartment was used to transport heroin, as
    opposed to any other kind of contraband, or that Navarrette
    ever used the compartment. We also note that the
    drug-sniffing dog did not alert to the compartment during the
    search.5
    Therefore, as did the district court, we conclude that the
    testimonial and physical evidence cannot support a finding of
    one kilogram.
    5
    While we have stated that a defendant’s mere access to equipment
    capable of producing a kilogram of cocaine “supports the jury’s verdict
    that it was reasonably foreseeable that the conspiracy involved 500 grams
    or more of cocaine,” 
    Rosales, 516 F.3d at 755
    , the government did not
    raise this argument on appeal, and therefore we do not address it here.
    “Our circuit has repeatedly admonished that we cannot manufacture
    arguments for an appellant.” Ind. Towers of Wash. v. Washington,
    
    350 F.3d 925
    , 929 (9th Cir. 2003) (quoting Devereaux v. Abbey, 
    263 F.3d 1070
    , 1082 (9th Cir. 2001)).
    22       UNITED STATES V. NAVARRETTE-AGUILAR
    D. The Pattern of Heroin Transactions
    We turn to the district court’s conclusion that the
    defendants’ pattern of transactions constituted circumstantial
    evidence, such that “the jury could have made a reasonable,
    non-speculative inference that Defendants must have agreed
    to distribute as much heroin as they could and that the
    distribution would have continued in a similar fashion.”
    Even if some hypothetical pattern of transactions were
    consistent and clear enough to infer a preexisting agreement
    to surpass a certain quantity, such is not the pattern before us.
    While the testimony of Equihua-Ramirez and Burns could
    prove repeated transactions over a period of eight weeks, the
    testimony did not show any consistency in those transactions,
    either with respect to amount or to frequency, from which a
    jury could reasonably infer an agreement to distribute a
    kilogram of heroin. This conclusion is underscored by the
    vague and equivocal nature of the testimony itself. Both
    witnesses at points contradicted themselves, and Burns
    repeatedly indicated that his memory was unreliable.
    Even construing the evidence in the light most favorable
    to the prosecution, the purchases in this case appear to have
    been ad hoc, and dependent on the level of demand at any
    given moment. The evidence showed that Equihua-Ramirez
    bought his supply of heroin from Navarrette only once he had
    sold the amount he had previously purchased; that Burns was
    Equihua-Ramirez’s biggest customer; that Burns only
    purchased heroin when there was sufficient demand; that
    demand was “different all the time”; and that there was a
    period of approximately two weeks out of a total period of ten
    weeks in which the heroin “went bad,” and Burns did not
    purchase any heroin.
    UNITED STATES V. NAVARRETTE-AGUILAR                  23
    Moreover, the testimony given at trial revealed that the
    whole arrangement was temporary and unstable. During the
    period alleged in the indictment, Equihua-Ramirez was
    effectively subbing for his friend. He testified that he had no
    intention of continuing once his friend returned, and, in fact,
    that he became so frustrated with the bad heroin that he
    considered quitting. Similarly, Burns repeatedly testified that
    he intended to quit selling heroin. In sum, it would be
    speculative to infer that the defendants agreed to any future
    transactions such that they would reach the one kilogram
    mark. Speculation cannot constitute substantial evidence.
    See Juan 
    H., 408 F.3d at 1277
    .
    Our conclusion is further supported by the Fourth
    Circuit’s holding in United States v. Hickman, 
    626 F.3d 756
    (4th Cir. 2010). In that case, the court held that substantial
    evidence did not support a conviction for conspiracy to
    distribute one kilogram of heroin where the past transactions
    and future, expressly agreed-upon transactions amounted to
    a maximum of 836 grams. 
    Id. at 766.
    In Hickman, as in this
    case, the government argued that the jury could conclude that
    the transactions proven were part of an “ongoing course of
    business.” 
    Id. at 768.
    The government in that case further
    argued that “[it was] clear that . . . [the defendant] would have
    continued” to distribute heroin. 
    Id. The Hickman
    court
    disagreed. It concluded that such a finding would come
    perilously close to impermissibly convicting the defendant of
    “hypothesized future bad acts,” and, moreover, that “[w]here
    no evidence exists to guide the trier of fact in determining the
    outer scope of a conspiracy, the trier may not simply guess at
    the magnitude or frequency of unknown criminal activity.”
    
    Id. at 768–69.
    24       UNITED STATES V. NAVARRETTE-AGUILAR
    In this case, the district court attempted to distinguish
    Hickman. In Hickman, the defendants agreed to or actually
    undertook three transactions, whereas in this case the number
    is at least ten. Therefore, the district court concluded that,
    unlike in Hickman, here there was sufficient evidence to
    “guide” the jury “as to the total amount that was involved in
    the conspiracy,” because there were “multiple purchases and
    multiple sales and thus, there were more than a ‘limited
    number of actual transactions.’” But though the evidence
    here showed more transactions than in Hickman, Hickman is
    not so easily distinguishable. In Hickman, the evidence
    supported a finding that the defendants had distributed a
    maximum of 836 grams over a period of four months, which
    is not much different than the up to 750 grams over a period
    of three months (according to the district court’s calculations)
    in this case. And here, like in Hickman, the argument that the
    co-conspirators would have distributed one kilogram if it had
    not been interrupted potentially allows a quantity finding to
    stand upon what Navarrette “would have continued to do[,]
    which, to the extent these hypothesized future bad acts were
    not captured by an agreement within the charged period, is
    clearly improper.” 
    Hickman, 626 F.3d at 768
    (internal
    quotation marks omitted). Such a theory impermissibly
    “invites the jury to speculate as to the amount of heroin
    involved in the conspiracy.” 
    Id. The government
    agrees that, should we conclude that
    substantial evidence does not support the jury’s verdict on the
    one kilogram quantity special finding, the error was not
    harmless and re-sentencing would be appropriate. While the
    special finding only resulted in a mandatory minimum
    sentence on Count One, the district court imposed an identical
    sentence on all counts. It is clear that the district court used
    this twenty-year sentence as the “starting point and the initial
    UNITED STATES V. NAVARRETTE-AGUILAR                           25
    benchmark,” Kimbrough v. United States, 
    552 U.S. 85
    , 108
    (2007) (quoting Gall v. United States, 
    552 U.S. 38
    , 49
    (2007)), and that, had the district court sentenced Navarrette
    absent the special finding and mandatory minimum, “it may
    have arrived at a different sentence,” see United States v.
    Munoz-Camarena, 
    631 F.3d 1028
    , 1031 (9th Cir. 2011).
    Therefore, we reverse the jury’s quantity finding, vacate
    Navarrette’s sentence on all counts, and remand for re-
    sentencing.6
    III.
    Navarrette challenges his conspiracy and substantive
    count convictions on the ground that the district court abused
    its discretion when it permitted the government to ask his
    sister, defense witness Mini Navarrette, about his prior
    Washington state convictions for drug trafficking and escape.
    The district court had originally granted a pre-trial motion
    in limine to exclude these convictions as overly prejudicial.
    However, on cross examination, Mini Navarrette stated that
    her brother could not drive because he did not have a license,
    and that “[she knew] that [her] brother did not do any drugs
    or anything.” The government argued that she had opened
    the door to impeachment, because she knew that Navarrette
    6
    Because Navarrette’s evidence insufficiency claim is limited to the
    jury’s quantity finding, we vacate his sentence, but we do not reverse the
    underlying conspiracy conviction under 21 U.S.C. § 841(a). As we have
    explained, “[t]he tainted drug quantity verdict does not affect the validity
    of the underlying conspiracy conviction because drug quantity was not an
    element of the charged conspiracy offense; rather, it . . . had to be
    submitted to a jury and proved beyond a reasonable doubt for the purposes
    of sentencing alone.” United States v. Vera, 
    770 F.3d 1232
    , 1249 (9th Cir.
    2014).
    26      UNITED STATES V. NAVARRETTE-AGUILAR
    could not drive because he was afraid that he would be pulled
    over and the outstanding warrant stemming from his escape
    discovered, and because she knew that he previously had
    been convicted and imprisoned. Navarrette objected, but the
    court allowed the government to question Mini Navarrette
    about her brother’s prior convictions.
    On cross-examination, a defense witness opens the door
    to impeachment by the prosecution if she “truly volunteer[s]”
    the impeachable testimony. 
    Id. at 1134
    n.1. Here, the
    government directly asked Mini Navarrette why her brother
    was unable to drive a car. The record does not support the
    government’s contention that Ms. Navarrette volunteered that
    her brother never used the car that was in her name and her
    sister-in-law’s name. But, Ms. Navarrette opened the door to
    impeachment later in her testimony, when she volunteered
    that she knew that her brother was not involved in drugs. Ms.
    Navarrette knew that her brother had previously been
    convicted and imprisoned, and had escaped. While it is
    possible that she did not know the exact nature of the
    conviction, the district court did not abuse its discretion in
    allowing the government to ask her about her brother’s prior
    convictions.
    Moreover, even if the district court did abuse its
    discretion, the error was harmless. As the government
    argues, Navarrette’s conviction was supported by phone
    records tying him to Equihua-Ramirez, as well as by
    Equihua-Ramirez’s testimony that Navarrette’s voice on a
    recorded call was the voice of his supplier, “Califas.” Ms.
    Navarrette’s testimony, intended to support the defense
    UNITED STATES V. NAVARRETTE-AGUILAR                 27
    theory that Navarrette had no involvement in the conspiracy,
    could not have overcome the weight of this evidence.
    Accordingly, we affirm the district court’s evidentiary ruling.
    AFFIRMED in part, REVERSED in part, VACATED
    in part, and REMANDED for re-sentencing.