 United States Court of Appeals
         FOR THE DISTRICT OF COLUMBIA CIRCUIT



Argued December 14, 2015              Decided June 24, 2016

                        No. 10-3083

                UNITED STATES OF AMERICA,
                        APPELLEE

                             v.

                JUAN JOSE MARTINEZ VEGA,
                ERMINSO CUEVAS CABRERA,
                       APPELLANTS


                 Consolidated with 10-3084


        Appeals from the United States District Court
                for the District of Columbia
                   (No. 1:04-cr-00446-51)
                   (No. 1:04-cr-00446-49)


    Richard K. Gilbert, appointed by the court, argued the
cause for appellant Martinez Vega. Manuel J. Retureta and
Gary M. Sidell, appointed by the court, argued the cause for
appellant Cuevas. With them on the briefs was Kristen Grim
Hughes.

    Michael A. Levy, Assistant U.S. Attorney, argued the
cause for appellee. On the brief were Ronald C. Machen Jr.,
U.S. Attorney at the time the brief was filed, and Randall W.
                              2
Jackson and Brian A. Jacobs, Assistant U.S. Attorneys.
Elizabeth Trosman, Assistant U.S. Attorney, entered an
appearance.

    Before: BROWN and MILLETT, Circuit Judges, and
GINSBURG, Senior Circuit Judge.

     PER CURIAM: Juan Jose Martinez Vega and Erminso
Cuevas Cabrera were indicted with more than 50 other
individuals for conspiring to commit crimes associated with
the importation, manufacture, and distribution of cocaine into
the United States. To date, only Martinez Vega, Cuevas, and
one other have stood trial. See United States v. Garcia, 757
F.3d 315 (D.C. Cir. 2014).

     The indicted individuals were allegedly affiliated with
the Fuerzas Armadas Revolucionarias de Colombia
(“FARC”), a “left-wing guerilla group that has waged a
violent insurgency against Colombia’s government for much
of the last fifty years.” Id. at 316. Though it initially
eschewed the drug trade as counterrevolutionary, the FARC
embraced the manufacture and exportation of cocaine in the
early 1980s as a lucrative means to fund its increasingly
ambitious military objectives. John Otis, The FARC and
Colombia’s Illegal Drug Trade, WILSON CENTER (Nov.
2014), at 3, https://www.wilsoncenter.org/sites/default/files/
Otis_FARCDrugTrade2014.pdf. By the 1990s and early
2000s, after the breakup of the famous Medellín and Cali
cartels, the FARC began to consolidate its control over the
coca fields and cocaine production. Id. at 4.

     Martinez Vega and Cuevas allegedly occupied different
roles within the cocaine trade. Martinez Vega’s role primarily
consisted of exporting cocaine and importing arms.
Throughout his association with the FARC, he was allegedly
                              3
responsible for exporting at least 11,000 kilograms of cocaine
and with supplying the FARC with 250 tons of ammunition,
explosives, and weapons. Cuevas, on the other hand,
allegedly operated a large cocaine laboratory that produced
thousands of kilograms of cocaine paste each week. In
addition to supervising that operation, Cuevas allegedly met
with FARC officials on several occasions to oversee the
shipment of coca base to his laboratory.

     After their capture and extradition to the United States,
Martinez Vega and Cuevas were tried for and convicted of
violating Title 21 of the United States Code, Sections 812,
952, 959, 960, and 963. Taken together, these sections
provide for the punishment of any person who knowingly or
intentionally conspires to import, manufacture, or distribute
five kilograms or more of cocaine into the United States. The
district court then sentenced Martinez Vega and Cuevas to
330 and 348 months’ imprisonment, respectively. These
defendants come before us now appealing their convictions
and sentences.

     Three categories of issues are raised in this appeal: the
joint issues, the Martinez Vega-specific issues, and the
Cuevas-specific issues. Both Martinez Vega and Cuevas
challenge the sufficiency of the evidence, the mens rea jury
instructions, and the district court’s denial of their motions
alleging prosecutorial misconduct. Martinez Vega challenges
several evidentiary rulings pertaining to identification
evidence, as well as the application of a “managerial”
sentencing enhancement. Finally, Cuevas challenges the
admission of certain evidence, the adequacy of the district
court’s curative instruction to the jury regarding stricken
testimony, the district court’s refusal to permit cross-
examination about witnesses wearing ankle monitoring
devices, and its application of certain sentencing
                              4
enhancements. Detailed discussions of the facts, evidence,
and standards of review will be set forth as necessary to
address each issue Defendants raise.

                       I. Joint Issues

     Martinez Vega and Cuevas together raise three arguments
for vacating their convictions: (i) the mens rea evidence was
insufficient; (ii) the mens rea jury instructions were
misleading; and (iii) the Government committed prejudicial
prosecutorial misconduct. We address each in turn.

                 A. Sufficiency of Evidence

     Defendants argue the evidence at trial was insufficient to
prove the mens rea element of their charged offense; that they
knew or intended the cocaine would end up in the United
States. See 21 U.S.C. § 952(a); id. § 959(a); id. § 960(a)(1),
(a)(3). In their view, not only did the Government fail to put
on any direct evidence of mens rea, the proffered
circumstantial evidence doesn’t justify the inference that
either of them knew the destination of the cocaine.

     Challenging a jury verdict for insufficient evidence
carries with it an “exceedingly heavy burden.” United States
v. Booker, 436 F.3d 238, 241 (D.C. Cir. 2006); see also
United States v. Morris, 576 F.3d 661, 666 (7th Cir. 2009)
(describing the burden as a “nearly insurmountable hurdle”).
To prevail, Defendants must convince the court that no
“rational trier of fact could have found the essential elements
of the crime beyond a reasonable doubt.” United States v.
Stadd, 636 F.3d 630, 636 (D.C. Cir. 2011). We review
sufficiency-of-the-evidence claims “in the light most
favorable to the government, drawing no distinction between
direct and circumstantial evidence, and giving full play to the
                               5
right of the jury to determine credibility, weigh the evidence
and draw justifiable inferences of fact.” United States v.
Dykes, 406 F.3d 717, 721 (D.C. Cir. 2005).

     We conclude the jury’s mens rea determinations were
justified by sufficient evidence. The Government
demonstrated several facts from which a rational juror could
reasonably infer intent or knowledge that the cocaine would
end up in the United States. First, it demonstrated that at least
half of the cocaine produced in Colombia is exported to the
United States, establishing a substantial probability that at
least some of the 11,000 kilograms of cocaine Martinez Vega
trafficked or the thousands of kilograms of cocaine paste
Cuevas manufactured each week was headed to the United
States. Second, several witnesses confirmed that, among the
FARC rank-and-file, it was a widespread and generally
known fact that the cocaine they handled was destined for the
United States. Maria Santiago and Hernan Santiago each
testified that the destination of these drugs (the United States)
was a topic of discussion among Cuevas’s subordinates at the
laboratory. And Alexis Perez offered similar testimony with
respect to Martinez Vega, that it was “something normal to
hear the comments that the coke was coming to the United
States because it was said that it is the country that most
consumes it.” These testimonies justify an inference that
those within both Martinez Vega’s and Cuevas’s operations
were generally aware of the intended destination. Third,
Martinez Vega and Cuevas had high-level roles in their
association with the FARC, which, in conjunction with the
previous point, justifies an inference that, given their rank
within the organization, they were even more likely to know
the destination than their subordinates. Martinez Vega was a
leader within the 16th Front of the FARC—he was an
important enough leader that the FARC provided security as
he conducted his operations. Cuevas was the “general
                              6
administrator” of a large cocaine laboratory where he
supervised about 80 workers and met with FARC officials to
coordinate product deliveries.

     These data points justify the jury’s inferences that both
Martinez Vega and Cuevas knew or intended the drugs would
end up in the United States. This is not a close question. In
fact, in United States v. Martinez, this court upheld a
conviction for conspiracy to import cocaine into the United
States against an insufficiency challenge based on evidence
that closely mirrors the evidence in this case. 476 F.3d 961,
963 (D.C. Cir. 2007). First, a former DEA Agent testified,
based on his extensive experience, that “almost every drug
operation that transports Colombian cocaine by land through
Central America intends to import the cocaine into the United
States.” Id. at 969. Second, there was direct evidence that
“many of the lower-level individuals involved with the . . .
shipment of cocaine knew [it] was headed to the United
States.” Id. And third, Martinez “supervised many key
aspects of the international transportation of this massive
shipment of cocaine.” Id. at 968.

     In response, Defendants stress a lack of direct evidence
of knowledge or intent, but that emphasis is unavailing. Our
review of insufficiency claims treats all evidence—direct or
circumstantial—the same. See Dykes, 406 F.3d at 721.
Moreover, this argument carries even less weight considering
their insufficiency claim alleges a lack of direct mens rea
evidence. In “most cases in which the defendant’s state of
mind is at issue, it may be near impossible to establish the
requisite mens rea through direct evidence,” and therefore
proof must be inferred from circumstantial evidence instead.
United States v. Schaffer, 183 F.3d 833, 843 (D.C. Cir. 1999).
As we have shown, the proffered circumstantial evidence is
                               7
sufficient to support the jury’s guilty verdicts, and
accordingly, we reject Defendants’ insufficiency claim.

                    B. Jury Instructions

     Martinez Vega and Cuevas also challenge the district
court’s jury instructions.       Specifically, they claim the
instructions failed to adequately convey that Defendants
“personally intended the cocaine be imported into the United
States or personally knew the cocaine would be imported into
the United States.” Defendants Br. 41. Defendants’ argument
focuses on the district court’s use of a “shorthand” description
of the mens rea requirement. In their view, the instructions
were “highly ambiguous” and “widen[ed] the meaning of
conspiracy” by “minimiz[ing] a defendant’s necessary
involvement.” Id. at 43.

     When reviewing a challenge to jury instructions, “[t]he
pertinent question is whether, taken as a whole, the
instructions accurately state the governing law and provide
the jury with sufficient understanding of those issues and
applicable standards.” United States v. Wilson, 605 F.3d 985,
1018 (D.C. Cir. 2010). While the propriety of a submitted
jury instruction is reviewed de novo, “the choice of language
to be used in a particular instruction . . . is reviewed only for
abuse of discretion.” Joy v. Bell Helicopter Textron, Inc., 999
F.2d 549, 556 (D.C. Cir. 1993).

     The district court’s instructions began with a recitation
of the charge, which included an accurate description of the
“knowing or intending” mens rea requirement. Then, the
court broke the Government’s burden into two parts. First,
the Government was required to demonstrate an “agreement
to import . . . or to manufacture and distribute five kilograms
or more of cocaine knowing and intending that it would be
                              8
imported into the United States.” Second, the Government
was required to demonstrate that Martinez Vega and Cuevas
“intentionally joined in that agreement.” Explaining further,
the district court stated the Government must prove “a
defendant participated in the conspiracy with knowledge of its
unlawful purposes, and with an intent to aid in the
accomplishment of its unlawful objectives.” Following this
robust description of the Government’s burden, the district
court concluded with a concise and accurate summary of the
mens rea requirement:

    Thus with respect to count one, if you find beyond a
    reasonable doubt that the defendant conspired to
    import any amount of cocaine into the United
    States, or to manufacture any amount of cocaine
    with the intent or knowledge that it would later be
    imported to the United States, then you should find
    the defendant guilty. If, however, you find that the
    government has not proven beyond a reasonable
    doubt that the defendant conspired to import any
    amount of cocaine into the United States or to
    manufacture and distribute any amount of cocaine
    with the intent or knowledge that it would later be
    imported to the United States, then you should
    [find] the defendant not guilty.

     On multiple occasions throughout the instructions, the
district court accurately and clearly explained the mens rea
requirement. And as we have stated, “[j]ury instructions are
proper if, when viewed as a whole, they fairly present the
applicable legal principles and standards.” Czekalski v.
LaHood, 589 F.3d 449, 453 (D.C. Cir. 2009).

    Defendants’ concern centers on the district court’s
shorthand description of the mens rea requirement, “that a
                               9
defendant participated in the conspiracy with knowledge of its
unlawful purposes, and with an intent to aid in the
accomplishment of its unlawful objectives.” This instruction,
however, was immediately preceded by a description of what
the conspiracy’s unlawful purposes and unlawful objectives
were—the importation, manufacture, and distribution of
cocaine with knowledge or intent that it end up in the United
States. That mens rea language is cumbersome, and the
district court’s decision to use a shorthand method of referring
to it did not render the mens rea instruction ambiguous,
especially considering that this shorthand language is
bookended by two unmistakably clear and entirely accurate
descriptions of the requirement. Jury instructions “must be
evaluated not in isolation but in the context of the entire
charge.” Jones v. United States, 527 U.S. 373, 391 (1999).
Taken as a whole, these instructions clearly informed the
jurors of the precise nature of the mens rea question before
them. Because the mens rea jury instructions unambiguously
and accurately reflected the state of the law, we hold the
district court did not err.

                C. Prosecutorial Misconduct

      Defendants allege the prosecutor improperly (i) appealed
to the jury to act as the “community conscience”; (ii)
expressed personal opinion regarding Defendants’ guilt; and
(iii) discussed the court’s overruling of a defense objection
during closing arguments. Each of these prosecutorial
misconduct claims fail. We address each in turn.

     First, Defendants contend the prosecutor’s references to
America’s drug culture and related problems in its closing
summation were unfairly “designed to inflame the passions or
prejudices” of jurors. Defendants Br. 47 (quoting United
States v. Johnson, 231 F.3d 43, 47 (D.C. Cir. 2000)).
                              10
Specifically, the prosecutor told the jury that “a lot of the
problems here in Washington D.C., in New York, in Detroit
where I grew up, can be traced right back to [drug
trafficking].” In Defendants’ view, the prosecutor perceived
the jury “might be [un]interested in Colombia’s drug
problems,” Defendants Br. 48, which led him to improperly
tie the Colombian drug trade to the American drug problem,
inviting the jury to act as the “community conscience.”

     To be sure, a suggestion that the jury act as the
“community conscience” can constitute error. In United
States v. Hawkins, our circuit warned it is improper to
“substitute emotion for evidence by equating, directly or by
innuendo, a verdict of guilty to a blow against the drug
problem.” 595 F.2d 751, 754 (D.C. Cir. 1978); see also
United States v. Solivan, 937 F.2d 1146, 1151 (6th Cir. 1991)
(holding an appeal to the jury to act as the community
conscience is improper when it is “calculated to incite the
passions and prejudices of the jurors”). This caution derives
from Viereck v. United States, 318 U.S. 236 (1943), in which
the Supreme Court held a prosecutor’s appeal to jurors’
patriotism during World War II was “wholly irrelevant to any
facts or issues in the case, the purpose and effect of which
could only have been to arouse passion and prejudice.” Id. at
247.

     But, critical to our disposition here, the Hawkins panel
held that such erroneous appeals may not warrant reversal “in
light of the relative strength of the case against the accused.”
595 F.2d at 754. Because “[t]he Government’s case against
appellant was strong indeed,” and the “instructions given by
the trial court sufficiently diluted any prejudice,” the panel
held it was not “an occasion on which reversal would be
appropriate.” Id. at 755; see also United States v. Barnett,
No. 97-3091, 1998 WL 203122, at *1 (D.C. Cir. April 8,
                                11
1998) (per curiam) (“[A]ppealing to the jury to ‘do the right
thing’ is not clearly erroneous when, as here, the Government
couples its argument that the jury should ‘do the right thing’
with specific references to the evidence in the record. . . .
Furthermore, the evidence presented at trial was sufficiently
probative of Barnett's guilt that any error that might have
occurred was not prejudicial.”).

     As it was in Hawkins, so it is here. Even if the prosecutor
erred in connecting Martinez Vega’s and Cuevas’s charges to
America’s drug problems, the error was harmless because the
case against the Defendants was “strong indeed.” Hawkins,
595 F.2d at 755. In light of that strong case, and also given
the district court’s instruction that “the statements and the
arguments of the lawyers are not evidence,” the prosecutor’s
appeal to the jury to act as the “community conscience” does
not warrant reversal.

     Second, Defendants contend the prosecutor improperly
interjected personal beliefs into his closing statement. “When
a prosecutor gives his personal opinion on the credibility of
witnesses or the defendant’s guilt . . . ‘such comments can . . .
jeopardize the defendant’s right to be tried solely on the basis
of the evidence presented to the jury.’” United States v.
Hampton, 718 F.3d 978, 983 (D.C. Cir. 2013) (quoting United
States v. Young, 470 U.S. 1, 18 (1985)). At various points
throughout the prosecutor’s summation, he spoke in the “first
person singular,” making such statements as, “I think the
evidence did prove that . . .”; “I think it is clear . . .”; “But if
you consider the recordings, and I think you should, it
becomes obvious . . .”; “I don’t know if I buy that . . .”; “I’m
not sure I buy it. I don’t think you should either . . .”; and
“I’m not even sure what to make of this argument.”
Defendants argue these statements violate the Supreme
                              12
Court’s injunction against prosecutors “interjecting personal
beliefs.” See Young, 470 U.S. at 7–8.

     Two of our sister circuits have directly confronted the
question whether speaking in the first person singular is a
ground for a new trial. See United States v. Nersesian, 824
F.2d 1294, 1328–29 (2d Cir. 1987); United States v. Carleo,
576 F.2d 846, 851–52 (10th Cir. 1978). Reviewing similar
statements as found here, the Nersesian court “stress[ed] that
it is a poor practice, one which this court has repeatedly
admonished prosecutors to avoid.” 824 F.2d at 1328. That
said, and despite recognizing “[i]t is well settled that it is
improper for a prosecutor to interject personal beliefs into a
summation,” the court nonetheless declined to reverse. Id.
Viewing the summation “as a whole,” the Second Circuit
examined whether the improper language “amount[ed] to
unacceptable vouching.”        Id.     Several considerations
prompted the court to conclude it did not. For one, the
“offending conduct was . . . limited to a relatively small
portion of an overall lengthy summation.” Id. Moreover, the
district court “instruct[ed] the jury that the lawyer’s
statements were not evidence,” and defense counsel made no
“contemporaneous objections.” Id. Also, the court concluded
“it can fairly be said that appellants’ convictions were the
result of the jury’s assessment of the evidence, not the result
of improper argument by the prosecutor.” Id.; see also United
States v. Restrepo, 547 F. App’x 34, 42 (2d Cir. 2013)
(warning prosecutors to avoid first-person formulations but
ultimately concluding “there [was] no likelihood that the jury
was misled about the argument the prosecutor was making”);
but see United States v. Eltayib, 88 F.3d 157, 173 (2d Cir.
1996) (concluding “not all uses of the pronoun ‘I’ are
improper” such as “I suggest that,” which “shie[s] away from
an outright endorsement”). In Carleo, the Tenth Circuit
charted a similar path. 576 F.2d at 851–52. Deeming
                                  13
improper the prosecutor’s first person formulation, the court
nonetheless determined the prosecutor “was neither
personally vouching for the credibility of the government
witness nor personally attacking the credibility of the
defendant,” nor was he “attempting to convey to the jury that
he somehow possessed information . . . to which the jury was
not privy.” Id. at 852. In light of these conclusions, the court
held the trial court did not abuse its discretion in denying a
motion for a new trial. See id.

     We join our sister circuits in admonishing prosecutors to
avoid the “use of the personal pronoun ‘I.’” Nersesian, 824
F.2d at 1328. It is poor practice and threatens the defendant’s
right to a fair trial. But as in Nersesian, Restrepo, and Carleo,
the prosecutor’s remarks here do not constitute reversible
error. As noted above, the district court instructed the jury
that the “statements and the arguments of the lawyers are not
evidence,” and the few offending statements were contained
within a very lengthy closing summation of the Government’s
strong case. While the prosecutor should have avoided the
personal pronoun, had he replaced “I” with slightly different
phrases like “the evidence shows” or “the record is clear
that,” he could have communicated a nearly identical
sentiment without any impropriety. 1 Cf. United States v.
Eltayib, 88 F.3d 157, 172 (2d Cir. 1996) (“The problem with

1
   In other words, slight stylistic cures can head off objections like
this at the pass. It is important to the integrity of the jury trial
process to avoid vouching or interjecting personal beliefs, but there
are plenty of proper ways to communicate what the prosecutor
attempted to say here. For example, compare the following
phrases. The prosecutor said: “I think the evidence did prove that .
. . .” An error-free way to say the same thing: “The evidence
proves . . . .” The prosecutor said, “I don’t know if I buy that . . .”,
but he could have said, “What you heard at trial casts doubt on that
. . . .”
                               14
a prosecutor’s use of the pronoun ‘I’ is that it ‘tends to make
an issue of [the prosecutor’s] own credibility, or to imply the
existence of extraneous proof.”). Moreover, Defendants’
counsel also failed to object to these statements at trial, so our
appellate touch is even lighter here than it otherwise might
have been. See United States v. Olano, 507 U.S. 725, 732
(1993). Accordingly, we conclude the jury’s guilty verdict
was a product of the Government’s strong case against
Martinez Vega and Cuevas, not the prosecutors stray
improper remarks.

     Third, Defendants argue that a PowerPoint slide
containing a reference to an overruled defense objection
constituted prosecutorial misconduct. Even assuming the
reference was error, Defendants fail to present any theory
whatsoever as to why it prejudiced them. Even their reply
brief contains no explanation, despite the Government’s
argument pointing out this critical defect. Reply Br. at 24.
(The entire response: “The Government offers no theory to
support presentation of a PowerPoint slide depicting the
overruling of a defense objection to the jury. Defendants
submit that none exists, especially in light of the district
court’s midtrial instruction.”). Without a showing of
“substantial prejudice,” an act of prosecutorial misconduct
cannot constitute reversible error. See United States v. Small,
74 F.3d 1276, 1280 (D.C. Cir. 1996). Defendants’ failure to
show any prejudice, let alone substantial prejudice, is fatal to
their prosecutorial misconduct claim.

             II. Issues Raised by Martinez Vega

     Martinez Vega individually challenges several of the
district court’s rulings pertaining to evidence identifying his
involvement in criminal activities. According to Martinez
Vega, such evidence was crucial to his eventual conviction
                               15
because the Government’s case against him relied primarily
on accepting both that a person nicknamed “Chiguiro” was a
significant member of the FARC’s 16th Front operation, and
that Martinez Vega was that individual. 2 Specifically,
Martinez Vega argues that the district court committed
reversible error in failing (i) to compel the Government to
correct the false testimony of DEA Intelligence Research
Specialist Francisco Garrido; (ii) to give “missing-evidence”
instructions to the jury regarding photo arrays that had been
used with certain witnesses; (iii) to sanction the Government
for its failure to timely disclose a photograph identifying
another man as “Chiguiro”; and (iv) to admit a prior
inconsistent statement by government witness Ignacio
Gonzales Jaramillo. Martinez Vega also appeals the district
court’s application of a “managerial role” sentencing
enhancement. We reject all of the evidentiary claims, but
vacate and remand Martinez Vega’s sentence to the district
court for further consideration.

           A. Failure to Correct False Testimony

    Former FARC member and prosecution witness Viviana
Ortiz testified on cross-examination that, during an interview
at the U.S. Embassy in Bogotá, she was shown some
photographs, one of which she identified as Martinez Vega by
the nickname “Chiguiro.” Defense counsel objected that the
prosecution had not previously disclosed Ortiz’s photographic
identification of Martinez Vega. The prosecutor disclaimed
any prior knowledge of the identification, and the district
court instructed the Government to “check with your records
and your agents to see if . . . somebody showed her a photo, if
you have a record of it.” S.A. 189–90. The following
2
  “Chiguiro” is another name for a capybara, “an extremely large,
semi-aquatic rodent, indigenous to South America.” Gov’t Br. 4.
                             16
morning, the prosecutor reported to the court his “suspicion”
that Ortiz had been shown photographs by an agent of the
Drug Enforcement Agency, but the Government “[didn’t]
have a record of that.” Id. at 212.

    During the defense case, Martinez Vega called Francisco
Garrido, a DEA Intelligence Research Specialist, and
questioned him about his interviews in Bogotá of former
FARC members, including Ortiz. On re-direct, defense
counsel confirmed with Garrido that Ortiz had identified
Martinez Vega as “Chiguiro.” When asked, “But you did not
actually show her photographs of Chiguiro, did you?” Garrido
responded, “I believe I did. I had a copy of the photo array
depicting your client.” S.A. 539.

     Martinez Vega’s counsel objected that Garrido’s
testimony was inconsistent with the Government’s prior
representation that “they did not have anybody who could
confirm or deny whether Ms. Ort[i]z was shown some
identifications [sic].” S.A. 539–40. The Government denied
any inconsistency, differentiating between a lack of records
about the identification and Garrido’s own recollection of the
events. The court stated that Martinez Vega could ask
additional questions if he wished to probe Garrido’s memory.

     During continued questioning by defense counsel,
Garrido confirmed that he had shown Ortiz a photo array and
claimed that the photographs “became part of the case folder.”
S.A. 544–46. At sidebar, defense counsel asked for the
photographs shown to Ortiz. The Government responded that
Garrido appeared to be testifying to “his belief,” but that
“there was only one photo array that was ever created”
including Martinez Vega’s picture, and Garrido likely “does
not have any photo array that is marked by Vivian[a] Ort[i]z,
                                 17
or that he recorded as being a specific one that she identified.”
Id. at 548. 3

     In a subsequent hearing outside the presence of the jury,
the district court allowed both sides to continue questioning
Garrido about the issue. Garrido confirmed that he created
only one photo array relating to Martinez Vega, but denied
any knowledge as to whether anyone had Ortiz “mark a photo
array.” S.A. 552. He testified that he did not record or make
any notes of Ortiz specifically marking or identifying any
photograph in the array. Garrido also admitted that he had
“no independent recollection” of whether or not Ortiz was
actually shown a photo array; his belief was based on the fact
that he had shown the photo array to “numerous people”
during the investigation. Id. at 553.

     The next day, Martinez Vega moved to dismiss the case
due to the Government’s failure to correct Garrido’s
testimony before the jury. The court denied the motion from
the bench, finding that the Government was not “deliberately
withholding information that’s false or allowing false
testimony to go forward uncorrected.” J.A. 1675. Martinez
Vega raised the issue again in his motion for a new trial. The
court once more denied the request, reasoning that, even if
Garrido had testified falsely about having shown Ortiz a
photo array, such testimony was immaterial and could not
have affected the jury’s judgment because there was sufficient
other evidence at trial regarding Martinez Vega’s identity.

     A claim that the Government violated the Fifth
Amendment by knowingly failing to correct false testimony is
reviewed de novo. See United States v. Mejia, 597 F.3d 1329,
1338 (D.C. Cir. 2010). The district court’s denials of motions
for a mistrial and for a new trial are reviewed for abuse of
3
    The “one” acknowledged photo array was previously admitted.
                              18
discretion. See United States v. Moore, 651 F.3d 30, 50 (D.C.
Cir. 2011) (mistrial); United States v. Becton, 601 F.3d 588,
594 (D.C. Cir. 2010) (new trial).

     Under Napue v. Illinois, 360 U.S. 264 (1959), the
Government “may not knowingly use false evidence” or
“allow[] it to go uncorrected when it appears,” id. at 269.
“This rule applies both when the testimony relates directly to
an essential element of the government’s proof and when it
affects the credibility of a crucial witness.” United States v.
Iverson, 637 F.2d 799, 801 (D.C. Cir. 1980), modified, 648
F.2d 737 (D.C. Cir. 1981). “The principle that a State may
not knowingly use false evidence, including false testimony,
to obtain a tainted conviction . . . does not cease to apply
merely because the false testimony goes only to the credibility
of the witness.” Napue, 360 U.S. at 269.

     Yet even if the prosecution either sponsored or failed to
correct false testimony, the grant of a new trial is not
automatic. See United States v. Burch, 156 F.3d 1315, 1329
(D.C. Cir. 1998); Giglio v. United States, 405 U.S. 150, 154
(1972). Rather, “a reviewing court must determine whether
‘the false testimony could in any reasonable likelihood have
affected the judgment of the jury.’” Burch, 156 F.3d at 1329
(quoting Giglio, 405 U.S. at 154). Put another way, “the fact
that testimony is perjured is considered material unless failure
to disclose it would be harmless beyond a reasonable doubt.”
United States v. Bagley, 473 U.S. 667, 680 (1985). 4

     As a preliminary matter, the Government’s effort to
portray Garrido’s testimony as merely an “equivocal”

4
  This standard is equivalent to the harmless-error standard for
constitutional error under Chapman v. California, 386 U.S. 18
(1978). See Bagley, 473 U.S. at 679 n.9.
                                 19
expression of his “belief” that he had shown Ortiz
photographs of “Chiguiro” (Gov’t Br. 48–49) strains credulity
and is heavily dependent on selectively parsing and
rearranging Garrido’s actual words. While Garrido did
initially say he “believe[d]” he had shown “photographs of
Chiguiro” to Ortiz, S.A. 539, he then proceeded to describe a
specific photo array, whether it included certain individuals,
and what he did with the array afterwards. Similarly, when
read in context, Garrido’s affirmative response to the question
whether he had shown Ortiz “any photographs” was not an
answer to a “broad and general question” about any random
assortment of pictures as the Government suggests. Gov’t Br.
49. Since Garrido had just testified about a photo array
depicting Martinez Vega and Ortiz’s identification of
Martinez Vega as “Chiguiro,” both defense counsel’s question
(“Now let me then ask you about the identification you told us
about. . . . When you met Ms. Ort[i]z on November 19, 2008,
did you show her any photographs?” S.A. 544–45) (emphasis
added), and Garrido’s answer (“Yes.” Id. at 545), by their
plain terms referred to the specific photographs in the
aforementioned photo array. 5

   Disappointingly, the Government knew or should have
known that this testimony was suspect. The Government had

5
   Moreover, the Government is wrong to assert that the district
court found that Garrido did not testify falsely about his use of the
photo array. To the contrary, the district court acknowledged the
“legitimate” questions regarding the credibility of Garrido’s
testimony, but ruled that the Government’s conduct did not warrant
dismissal in light of the “multiple identifications of Mr. Martinez
Vega by other individuals” at trial. S.A. 922–23. Later, in ruling
on Martinez Vega’s motion for a new trial, the court expressly
declined to make any determination as to whether Garrido’s
testimony was false, finding that it was not material even if false.
                                20
previously disclaimed any prior knowledge of a photo-array
identification by Ortiz and reported to the court that it had no
record of anyone showing Ortiz photographs.                  The
Government thus should have been on full alert as soon as
Garrido started testifying to a different story. The hearing
conducted by the district court, outside of the jury’s presence,
spotlighted Garrido’s inaccuracies. 6              Hair-splitting
distinctions in degree of falsity and inaccuracy should not be
the currency of federal prosecutors. See Napue, 360 U.S. at
269 (“[A]lthough not soliciting false evidence,” the
government is bound to correct it “when it appears.”).

     The only thing that saves the Government is that
Garrido’s testimony could not “in any reasonable likelihood
have affected the judgment of the jury.” Napue, 360 U.S. at
271.     Martinez Vega argues that permitting Garrido’s
testimony to remain uncorrected not only bolstered the
substantive testimony of Ortiz, but also reinforced the overall
credibility of both witnesses. That is, a revelation that
Garrido’s testimony was false might have cast doubt on the
general reliability of both Ortiz and Garrido, particularly
given other inconsistencies in their testimonies. And that in
turn might have colored the jury’s acceptance or rejection of
Garrido’s and Ortiz’s testimony on other matters.

6
    See S.A. 553 (Q: “So, when you testified that you believed that
the photo array . . . that you believed was shown to Ms. Ortiz was
in the case file, can you explain what you were talking about?” A:
“I thought that the photo array—that she was shown a photo array
and that she had markings, but she didn’t [sic].” Q: “Well, can you
. . . state with certainty that Ms. Ortiz was actually shown a photo
array?” A: “I don’t have an independent recollection whether she
was or wasn’t. I really don’t remember.”); id. at 555 (Q: “So, as
you sit here today, did you or did you not show Viviana Ortiz a
photo array?” A: “As I sit here today, I don’t have a recollection
whether I did or I did not.”).
                              21
     That line of reasoning does not hold up given the record
in this case. First, Ortiz’s identification of Martinez Vega
during the alleged photo array presentation was of dubious
relevance, given that Ortiz had repeatedly identified Martinez
Vega and connected him to the nickname “Chiguiro” earlier
in the trial. Indeed, she identified him by that moniker at the
very start of her testimony, and again while being shown
video footage of guerillas crossing a river “with Chiguiro.”
Importantly, Ortiz based those in-court identifications on her
frequent, personal, and direct observations of Martinez Vega
working with the FARC. She recounted, for example,
providing security for Martinez Vega while he and his men
transported weapons and cocaine base. She also testified to
seeing him speak with various FARC commanders and move
drugs and weapons to and from camp. At one point, Ortiz
recalled how she and other FARC members even ate lunch at
Martinez Vega’s house. Given all that, the reference to a
photo array was just gilding the lily.

     Second, even if the jury had completely disregarded
Garrido and Ortiz as unreliable witnesses, multiple other
witnesses provided similar testimony. For example, like
Ortiz, Mauricio Parra Diaz repeatedly identified Martinez
Vega as “Chiguiro” and testified that he saw him transporting
cocaine and weapons for the FARC. Parra Diaz also
confirmed, as did Ortiz, that Martinez Vega carried a pistol—
something only guerillas and drug traffickers were permitted
to do in the 16th Front—and testified that he was present
when Front Leader Negro Acacio announced the news of
Martinez Vega’s arrest. Likewise, Eugenio Vargas Perdomo
identified Martinez Vega as “Chiguiro,” and testified that they
lived and worked together, trafficking cocaine and buying
uniforms, weapons, and ammunition for the 16th Front. And
Luis Restrepo testified that Martinez Vega was “Chiguiro,”
                              22
and that he witnessed Martinez Vega repeatedly exchange
weapons for cocaine with Negro Acacio.

    Garrido’s testimony, too, generally reiterated other
evidence at trial. Garrido explained that Martinez Vega,
during his extradition flight to the U.S., stated that his
nickname was “Chiguiro” and described having moved
several tons of cocaine, weapons, and supplies for the FARC.
But Carlos Gonzales Jaramillo, a colonel in the Colombian
army, also testified that Martinez Vega made similar
confessions to him, including that he was “Chiguiro” and that
he transported several tons of cocaine, as well as uniforms
and weapons, for the FARC.

     Accordingly, looking at the evidence in the record as a
whole, there is no “reasonable likelihood” that the photo-array
segment of Garrido’s testimony, even if false, could have
altered the outcome of the case. Cf. Giglio, 405 U.S. at 154–
55 (reversing where “the Government’s case depended almost
entirely on [the perjuring witness’s] testimony; without it
there could have been no indictment and no evidence to carry
the case to the jury”). Because the false testimony was not
material, the district court’s refusal to grant a mistrial or a
new trial was not an abuse of discretion.

             B. Missing-Evidence Instructions

     Another government witness, Mauricio Parra Diaz,
testified to being shown photographs at the U.S. Embassy in
Colombia by the DEA and selecting Martinez Vega as
“Chiguiro.” Outside the presence of the jury, DEA Special
Agents Cesar Medina and Daniel Dyer testified that a photo
array had been shown to numerous potential witnesses in
Colombia. However, the agents had no specific recollection
of the people who were shown the array, and the Government
kept no record of that information or of any identifications the
                             23
witnesses made. In fact, Medina confirmed that “the
understanding” within his office was that he “would keep no
record of this,” but simply call Dyer in the event of an
identification, J.A. 1000, and Dyer, for his part,
acknowledged that he did not make records of such calls.
Medina also testified that the photo array he used was kept in
a folder in the DEA’s Bogotá Country Office, but that he
believed it had since been shredded because the office
“shred[s] the photo arrays, because it is not needed any more
for that particular interview [sic].” Id.

     In light of that testimony, Martinez Vega requested the
following jury instruction:

    Both Ms. Ortiz and Mr. Parra Diaz have testified that
    they were shown photographs of individuals at the
    United States Embassy in Bogota and that they
    identified a photograph of Martinez Vega as that of
    the person they have each identified as “Chiguiro.”
    The United States has no records or other
    information that would corroborate this testimony. If
    photographs were shown to the witnesses for
    purposes of identification, the Government would be
    obligated to preserve such photographs, as well as
    any record of what the witnesses may have said at
    the time of their identifications. The United States
    has no such photographs or records.

J.A. 1054.

     A third witness, Luis Restrepo, testified that he was
shown photographs that “included . . . Mr. Chiguiro,” whom
he identified in court as Martinez Vega. J.A. 1191. Garrido
testified that he showed Restrepo a photo array depicting
Martinez Vega and that he “thought [the photos] were filed in
                              24
the case folder.” Id. at 1362. Again, no such photographs
were produced by the Government.

    Martinez Vega requested another instruction regarding
Restrepo’s identification:

    If photographs shown to Mr. Restrepo in this case
    were only within the power of the government to
    produce, and were not produced by the government,
    and their absence has not been sufficiently explained,
    then you may, if you deem it appropriate, infer that
    the photographs would have been unfavorable to the
    government.

J.A. 1054–55. The district court declined to give either
instruction, citing no evidence of bad faith on the part of the
Government regarding the loss or destruction of the
photographs and the fact that “these were not really
identification procedures” in which the “only way [the
witnesses] could ever identify” Martinez Vega was through
the photo array. Id. at 1698–1700.

     The district court’s decision withholding a missing-
evidence instruction is reviewed for abuse of discretion.
United States v. West, 393 F.3d 1302, 1309 (D.C. Cir. 2005),
abrogated on other grounds by Burgess v. United States, 553
U.S. 124 (2008); see also United States v. Tarantino, 846
F.2d 1384, 1404 (D.C. Cir. 1998) (describing standard of
review for denial of analogous missing-witness instruction).
A missing-evidence instruction “is appropriate if it is
peculiarly within the power of one party to produce the
evidence and the evidence would elucidate a disputed
transaction.” West, 393 F.3d at 1309; see also United States
v. Williams, 113 F.3d 243, 245 (D.C. Cir. 1997) (foundation
for analogous missing-witness instruction). “When these two
requirements are met, jurors may be instructed that the
                               25
controlling party’s failure to produce the evidence permits
them to draw the inference that the evidence would have been
unfavorable to that party.” Id.

     Federal Rule of Criminal Procedure 16, the Jencks Act,
18 U.S.C. § 3500, and Brady v. Maryland, 373 U.S. 83
(1963), all impose duties on the Government to disclose
certain materials and evidence to criminal defendants. In
United States v. Bryant, 439 F.2d 642 (D.C. Cir. 1971), this
court held that those duties to disclose included a correlative
duty to preserve that evidence in the first place, since “[o]nly
if evidence is carefully preserved during the early stages of
investigation will disclosure be possible later,” id. at 651.
Accordingly, Bryant instructed that the Government must
“promulgate[], enforce[] and attempt[] in good faith to follow
rigorous and systematic procedures designed to preserve all
discoverable evidence gathered in the course of a criminal
investigation,” or else risk the imposition of sanctions “for
non-disclosure based on loss of evidence.” Id. at 652.

     Martinez Vega argues that, under Bryant, the
Government was obligated to retain the photographs used in
the witness identifications, as well as verbatim records of any
statements the witnesses may have made at the time. The
problem for Martinez Vega is that the Supreme Court’s
subsequent decision in Arizona v. Youngblood, 488 U.S. 51
(1988), narrowed the Government’s constitutional obligations
regarding the preservation of evidence. Specifically, the
Court held that “the Due Process Clause of the Fourteenth
Amendment, as interpreted in Brady, makes the good or bad
faith of the State irrelevant when the State fails to disclose to
the defendant material exculpatory evidence.” Id. at 57. But
if “no more can be said” about the evidence “than that it could
have been subjected to tests, the results of which might have
exonerated the defendant,” there is no denial of due process
                               26
unless a criminal defendant can demonstrate the
Government’s bad faith. Id. at 57–58. Youngblood thus
confines the Due Process Clause to superintending only those
cases in which the missing evidence is material and
exculpatory or in which “the police themselves by their
conduct indicate that the evidence could form a basis for
exonerating the defendant.” Id. at 58.

     Following Youngblood, this court has held that Bryant, at
least with respect to due process claims based on missing
evidence the exculpatory value of which is unclear, is “no
longer good law.” In re Sealed Case, 99 F.3d 1175, 1178
(D.C. Cir. 1996); see also United States v. McKie, 951 F.2d
399, 403 (D.C. Cir. 1991) (rejecting reliance on Bryant
because “due process claims . . . are now governed by the
standards enunciated in Arizona v. Youngblood”).

     Martinez Vega nonetheless argues that Bryant provides
the relevant standard because his objection is grounded not in
the general protections of the Due Process Clause, but in the
Government’s specific obligations under Federal Rule of
Criminal Procedure 16, the Jencks Act, and Brady. 7
Alternatively, Martinez Vega contends that, even under
Youngblood, missing-evidence instructions were warranted
because the Government’s bad faith can be inferred.
Specifically, despite every incentive to maintain careful
records of the identifications for subsequent use at trial, the

7
  Whether Youngblood forecloses the application of Bryant in the
context of Jencks Act claims is unsettled. See McKie, 951 F.2d at
403 (leaving unaddressed “the continuing vitality of Bryant in its
original context regarding claims under the Jencks Act”). But see
United States v. Thomas, 97 F.3d 1499, 1503 (D.C. Cir. 1996)
(noting that “the actual holding in [Bryant] did not rest on the
Jencks Act” since “the court did not decide that the missing
[evidence] constituted a Jencks Act statement”).
                             27
DEA agents kept no such documentation. Martinez Vega
emphasizes that the exculpatory value of the untested physical
evidence in Youngblood was unknown to the agents. See 488
U.S. 56 n.* (noting that the defendant “has not shown that the
police knew the [missing evidence] would have exculpated
him when they failed to” preserve it). Here, by contrast, the
agents necessarily knew the results of their photo-array
presentations and thus had actual knowledge whether such
documents were actually (and not just potentially)
exculpatory. The conspicuous absence of evidence with
clearly “knowable” exculpatory value, Martinez Vega
concludes, points strongly to bad faith, especially given that
the same DEA agents apparently preserved marked photo
arrays used in identification procedures conducted with other
individuals.

     The Government’s failure to retain records for witness
identifications—records for which the inculpatory or
exculpatory value seems obvious—is troubling. But even
assuming Youngblood applies, the erroneous denial of a
missing-evidence instruction will not require reversal if the
error is harmless. See United States v. Glenn, 64 F.3d 706,
710 (D.C. Cir. 1995). And in that regard, Martinez Vega fails
to identify how that mistake affected his defense or had a
substantial and injurious effect on his trial. Kotteakos v.
United States, 328 U.S. 750, 765 (1946). Indeed, Martinez
Vega’s identity as “Chiguiro” was established by the
testimony of multiple witnesses based on in-person
observations and interactions, wholly independent of the
missing photo arrays.        See, e.g., supra pp. 21-22.
Accordingly, any error by the district court in declining to
issue missing-evidence instructions was harmless.
                               28
               C. The “Chiguiro” Photograph

     Six weeks before trial, the Government turned over a
document obtained from Colombian Military Intelligence.
The document is a printout of a PowerPoint-type slide
containing photographs of four men. Three of the men are
labeled FARC commanders in the 16th Front. The fourth
photograph shows a person (not Martinez Vega) in full
military uniform and is labeled “Angel Leopoldo Lopez, aka
Chiguiro.” J.A. 1786.

    At trial, the Government called Major Guillermo Rios,
Colombian Military Intelligence’s “chief of analysis” for the
16th Front, who testified that the only names associated with
“Chiguiro” that the Colombian military had in “the files [he]
looked [at]” and “in the files that [he] received” were “Juan
Jose Martinez Vega” and “Gentil Alvis Patiño.” J.A. 1149. 8

     On cross-examination, the defense showed the printout
with the “Chiguiro” photo to Rios, but he denied ever having
seen it before. Martinez Vega then filed a motion seeking all
exculpatory evidence pertaining to the printout. A few days
later, the Government advised Martinez Vega by letter that
the slide from which the printout came had been found in an
electronic storage file of the DEA Bogotá Country Office, but
that none of the current agents of that office could identify its
origin. However, agents who had previously worked in the
office stated that the slide was given to them by Colombian
intelligence around 2001 in the context of large transmissions

8
  The indictment charged Martinez Vega under the aliases of
“Gentil Alvis Patiño” and “Chiguiro,” but the defense demonstrated
that Patiño was another individual with ties to other alleged FARC
leaders, and the Government eventually stipulated that Colombian
identification documents existed for a different individual named
Patiño.
                             29
of information on FARC members. The letter further
explained that the Government’s contacts with the Colombian
military and intelligence were also unaware of the origin of
the “Chiguiro” photograph, the slide, or the information on
the slide.

     Martinez Vega argued that it was misleading for the
Government to ask Rios about his “files” and elicit that no
other person had been identified as “Chiguiro” when the
Government “knew that, at some point in time, an agency of
Colombian Military Intelligence which reported to the office
occupied by Rios, had reached the opposite conclusion.” J.A.
1381. Martinez Vega therefore proposed that the following
stipulation be provided to the jury:

    The parties stipulate that Defendant Martinez [sic]
    Exhibit 3 is a document which was found in an
    electronic storage file of the Drug Enforcement
    Administration’s Bogota Country Office. It is
    believed that it was transmitted, as part of a larger
    transmission of information, by Colombian Military
    Intelligence in or around 2001. The DEA has no
    further information about the origin of the document,
    the photographs contained on it, or accuracy of the
    captions to the photographs.

Id. The Government refused to so stipulate. The court also
declined to admit the printout from the slide into evidence
since it had not been identified by any witness and had not
been verified or authenticated in any way. Id. at 1688–89.

     In his motion for a new trial, Martinez Vega argued that
the Government’s delayed disclosure of the printout “at a time
and under circumstances when Defendant could not ascertain
the factual basis for the document” violated Brady. J.A. 1780.
He also argued that the Government compounded the breach
                               30
by questioning Major Rios in a misleading way, and that the
district court failed to remedy those infractions. The court
denied the motion, finding that the printout and the sought-
after information were not material.

    We review the district court’s denial of a motion for a
new trial for abuse of discretion, but evaluate de novo the
court’s assessment of whether the Government breached its
obligations under Brady. See United States v. Oruche, 484
F.3d 590, 595 (D.C. Cir. 2007).

     The district court did not err in denying a new trial
because there is no reasonable prospect that earlier disclosure
of the printout or any additional information about it would
have affected the trial’s outcome. Brady requires the
Government to disclose, upon request, “evidence favorable to
an accused . . . where the evidence is material either to guilt or
to punishment.” 373 U.S. at 87. The “touchstone of
materiality” is “‘a reasonable probability’ of a different
result.” Kyles v. Whitley, 514 U.S. 419, 434 (1995) (quoting
Bagley, 473 U.S. at 678). The bottom-line question “is not
whether the defendant would more likely than not have
received a different verdict with the evidence, but whether in
its absence he received a fair trial, understood as a trial
resulting in a verdict worthy of confidence.” Kyles, 514 U.S.
at 434. “A ‘reasonable probability’ of a different result” turns
on whether the Government’s suppression of evidence
“‘undermines confidence in the outcome of the trial.’” Id.
(quoting Bagley, 473 U.S. at 678).

     In this case, for evidence that there was another
“Chiguiro” affiliated with the FARC to have made any
difference, the Government’s case would have to be heavily
reliant on Martinez Vega’s use of the nickname. But the
record evidence bucks that notion. Multiple witnesses who
                              31
knew Martinez Vega—either as “Chiguiro” or not—identified
him repeatedly in person and testified to seeing him
transporting weapons or cocaine and interacting with leaders
of the 16th Front. The district court found that those
witnesses “did not have fleeting glimpses of the defendant.”
J.A. 2145. Rather, “they worked with him, ate meals with
him, and even lived with him,” leaving “little room for doubt
about the reliability of their identifications of him as the
person they observed engaging in conspiratorial acts.” Id.
Those witnesses personally knew Martinez Vega and
observed him in the relevant circumstances. For those
witnesses, the name that Martinez Vega went by was largely
beside the point. Thus, any revelation that another individual
affiliated with the FARC was also referred to as “Chiguiro”
would not plausibly have had any effect on the outcome of the
trial.

              D. Prior Inconsistent Statement

     Colonel Ignacio Gonzales Jaramillo of the Colombian
military testified that he interviewed Martinez Vega in a
Venezuelan prison.        According to Gonzales Jaramillo,
Martinez Vega denied being involved in the FARC during the
initial portion of the interview, which was videotaped. But
after the video camera was turned off, Martinez Vega
allegedly began admitting his involvement with the
organization. Gonzales Jaramillo testified that the camera
was off for “20, 25 minutes, maybe half an hour” during the
interview. J.A. 1116.

     Following the interview, the Colonel documented the
details of the interview. In pertinent part, his report states:

    Upon asking [Martinez Vega] about his ties to
    kidnapping and drug trafficking, he denied all
    involvement at any time. . . .
                             32
    The interview continued on the same line for almost
    2 hours, denying his relationship with the terrorist
    organization and denying his ties to kidnapping and
    drug trafficking.

    As the conversation progressed, facts from his past
    life were brought up, thanks to information obtained
    by intelligence work and, in other cases, supplied by
    the informant who accompanied the delegation. The
    presentation of facts made the subject begin to
    contradict himself.

J.A. 1479.

     During cross-examination, defense counsel confronted
Gonzales Jaramillo with the apparent contradiction between
his testimony that Martinez Vega was cooperative during the
20 or 30 minutes that the camera was off, and the report’s
statement that Martinez Vega denied any connection to the
FARC for nearly two hours. The Colonel explained that the
two-hour period referred to the entire time he was with
Martinez Vega “from the first moment I saw him until we
started talking because until the cameras were off, we didn’t
start a conversation.” J.A. 1119; see also id. at 1120 (“Yes,
from the first time we saw each other until about—until we
sat down. Less than two hours, but yes, that’s how it was.”).

     Martinez Vega moved to admit into evidence a copy of
Gonzales Jaramillo’s interview report as a prior inconsistent
statement. He contends that, because the videotaped portion
of the interview did not get into the subject of the FARC,
drugs, or kidnapping, the two-hour discussion of those topics
necessarily did not begin until after the camera was turned
off.
                               33
     The district court denied the motion, finding that it was
“not clear” that the interview report amounted to a prior
inconsistent statement since it was ambiguous whether “the
two hours” in the report referred to the length of the entire
interview, or only the time during which the camera was
turned off. J.A. 1682. The court also noted that “the jury has
heard at length . . . what allegedly the report said” during
cross-examination of Gonzales Jaramillo, id., and expressed
concern that the report elsewhere contained “exculpatory
statements of the defendant not subject to cross-examination,”
id. at 1683.

      The district court’s admission or exclusion of evidence is
reviewed for abuse for discretion. See United States v.
Morgan, 581 F.2d 933, 936 (D.C. Cir. 1978). Federal Rule of
Evidence 613(b) permits the use of a witness’s prior
inconsistent statement for impeachment “if the witness is
given an opportunity to explain or deny the statement and an
adverse party is given an opportunity to examine the witness
about it.” While “direct contradiction is not essential,” the
trial court “has discretion in determining whether testimony is
inconsistent with a prior statement.” 28 Wright & Gold,
Federal Practice & Procedure, § 6203 (2d ed. 2012); see
Grunewald v. United States, 353 U.S. 391, 423 (1957) (“[T]he
question whether a prior statement is sufficiently inconsistent
to be allowed to go to the jury on the question of credibility is
usually within the discretion of the trial judge.”).

     The district court did not abuse its discretion in
concluding that there was no material inconsistency between
Gonzales Jaramillo’s report and his testimony. Gonzales
Jaramillo clarified on cross-examination that, although he did
not explicitly inquire about the FARC, drugs, and kidnapping
during the videotaped portion of the interview, he did ask
Martinez Vega why he had been arrested in Venezuela. J.A.
                               34
1489–90 (“Why do they have you here?”; “Where did they
nab you?”; “Alright, but why?           In other words, the
Venezuelan authorities arrived and what were you doing at
the time?”). In response, Martinez Vega denied knowledge as
to why the police had picked him up. Id. (“I don’t know.
They nabbed me at the farm where I was working and brought
me here.”; “I was fixing something of a pool and some
kiosks.”). Martinez Vega’s responses to additional questions
about his presence and activities in Venezuela were likewise
vague and noncommittal. Id. at 1492 (Q: “How long have
you been in Venezuelan territory?” A: “Since last year.” Q:
“Can you please be more precise . . .?” A: “I don’t remember
exactly.” . . . Q: “Beginning of the month . . . beginning of the
year.” A: “When a man brought me here to get papers and
help him work.” Q: “What man”?); id. at 1494 (Q: “Did you
go to Caracas?” A: “In a car.” Q: “In a car? With whom?”
A: “With that man.” Q: “What’s the man’s name?” A:
“Alberto.” Q: “What does Alberto look like? . . . Alberto
what?” A: “I don’t know his last name.”). Martinez Vega
was also cagey about a wound in his neck, stating at first that
it was from an operation, then explaining that he had been
shot, but by whom he did not know.

     Those kinds of unresponsive exchanges are reasonably
consistent with testimony that Martinez Vega “did not
accept—he didn’t volunteer his information as to his FARC
membership,” J.A. 1119, and that “he did deny his
participation . . . [h]e kept saying that he had nothing to do, he
owed nothing,” id. at 1120. They are also not inconsistent
with the general statement in the report that Martinez Vega
denied his relationship to the FARC or any involvement in
kidnapping and drugs for two hours, particularly since he had
been arrested in Venezuela for those very things.
                               35
     Accordingly, the district court did not abuse its discretion
in determining that the report was not a prior inconsistent
statement and declining to admit it under Rule 613(b).
Moreover, even if the exclusion of the report were error, it
was harmless given that any perceived contradiction between
the contents of the report and the Gonzalez Jaramillo’s
testimony was fully aired for the jury during cross-
examination. See United States v. Davis, 181 F.3d 147, 149
(D.C. Cir. 1999) (evidentiary exclusion harmless because,
“during the cross-examination of [the witness] the jury heard
word-for-word what he said at the suppression hearing” and
therefore the court’s refusal to admit the transcript “in no way
prejudiced [defendant] or impaired his defense”); United
States v. Bogle, 114 F.3d 1271, 1275 (D.C. Cir. 1997) (court’s
refusal to exclude prior written statement of witness was
“clearly harmless” where defense was able to impeach the
witness about the statement on cross-examination).

                E. Sentencing Enhancement

    At sentencing, the district court increased Martinez
Vega’s base offense level by three for being a “manager or
supervisor” in the narcotics conspiracy. Martinez Vega
challenges the enhancement for lack of evidence that he
supervised other participants in the conspiracy.

     In reviewing a sentencing decision, “[p]urely legal
questions are reviewed de novo; factual findings are to be
affirmed unless clearly erroneous; and we are to give due
deference to the district court’s application of the [sentencing]
guidelines to facts.” United States v. Day, 524 F.3d 1361,
1367 (D.C. Cir. 2008) (internal quotation marks omitted).
The Government must demonstrate that a sentencing
enhancement is warranted by a fair preponderance of the
evidence, United States v. Bapack, 129 F.3d 1320, 1324 (D.C.
                              36
Cir. 1997), though that evidence may be circumstantial,
United States v. Graham, 162 F.3d 1180, 1183 (D.C. Cir.
1998).

     Section 3B1.1 of the Sentencing Guidelines permits the
district court to increase a defendant’s base offense level due
to his “aggravating role” in an offense. U.S.S.G. § 3B1.1.
“The magnitude of the enhancement varies with the
culpability of the defendant,” Graham, 162 F.3d at 1182–83,
as well as the scope of the criminal activity. As relevant here,
a defendant is subject to a three-level increase for being “a
manager or supervisor (but not an organizer or leader)” of a
criminal activity that “involved five or more participants or
was otherwise extensive.” U.S.S.G. § 3B1.1(b); see Graham,
162 F.3d at 1183.

     The commentary to Section 3B1.1 instructs the
sentencing court to consider several factors in determining
whether to apply an enhancement, including “the exercise of
decision making authority, the nature of participation in the
commission of the offense, the recruitment of accomplices,
the claimed right to a larger share of the fruits of the crime,
the degree of participation in planning or organizing the
offense, the nature and scope of the illegal activity, and the
degree of control and authority exercised over others.”
U.S.S.G. § 3B1.1 application note 4.

     “Mere control over a scheme rather than over a
participant in a scheme” is not enough to warrant an
aggravating role enhancement. Bapack, 129 F.3d at 1324
(internal quotation marks omitted). Instead, the guidelines
require that “the defendant must have been the organizer,
leader, manager or supervisor of one or more participants” in
the criminal activity. U.S.S.G. § 3B1.1 application note 2
(emphasis added). A “participant” is a “person who is
                               37
criminally responsible for the commission of the offense, but
need not have been convicted.” Id. § 3B1.1 application note
1. An individual is “‘criminally responsible’ under § 3B1.1
only if ‘he commit[s] all of the elements of a statutory crime
with the requisite mens rea.’” United States v. McCoy, 242
F.3d 399, 410 (D.C. Cir. 2001) (quoting Bapack, 129 F.3d at
1325). “This does not mean, however, that to qualify as a
‘participant’ a person must be found criminally responsible as
a principal or culpable in the same crime of which the
supervising defendant was convicted.” Bapack 129 F.3d at
1325 (emphasis added). Instead, “a party who gives knowing
aid in some part of the criminal enterprise is a ‘criminally
responsible party.’” Id. (quoting United States v. Hall, 101
F.3d 1174, 1178 (7th Cir. 1996)) (emphasis added).

     Accordingly, to justify the three-level managerial-role
enhancement, the Government had to prove by a
preponderance of the evidence that Martinez Vega (i)
managed or supervised (ii) at least one “participant” who was
criminally responsible for an offense (iii) in a criminal
activity that involved five or more participants or was
otherwise extensive. The district court adequately assessed
the first element, but failed to make the required findings on
the second and third elements.

     As to the first element, the district court pointed to record
evidence showing that Martinez Vega “had significant
responsibility given to him by the leadership of the FARC”
and exercised “decision-making authority on selling these
drugs, and transferring them for weapons and getting the
weapons.” Sentencing Tr. 45–46. The court recounted the
testimony of Parra Diaz, which had “suggest[ed] that the
defendant may have a troop” and had described “Mr.
Martinez Vega as having guards . . . suggest[ing] that there
were many supervised.” Id. at 40. The court also relied upon
                               38
Ortiz’s testimony to the effect that “the person in charge of
that group of drivers and all was ‘Chiguiro,’ that is the
defendant,” id. at 42, and Restrepo’s testimony that “the
defendant was like our commander, our immediate
commander,” and “the defendant actually assigned them
where to go,” id. at 42–43. The record thus amply supported
the district court’s conclusion that Martinez Vega had
sufficient control and authority over other individuals to be a
manager or supervisor.

     But absent from the district court’s analysis is any
consideration of the second element necessary for the
enhancement:       whether any of the persons allegedly
supervised by Martinez Vega qualified as a “participant”
under Section 3B1.1. The parties specifically contested that
issue at the sentencing hearing. The Government asserted that
“any individuals who are engaged in moving cocaine and
weapons to a guerilla group in the jungles in Colombia would
have, by definition, been aware of the criminal nature of the
their activities, and they would have been participants as
understood by the guidelines.” Sentencing Tr. 26. Martinez
Vega countered that the Government had not shown that the
workers who helped him load and unload sacks would have
known that the sacks contained cocaine base or that it was
being exported to the United States. Id. at 37. The district
court, however, did not address the issue and made no finding
that one or more of those supervised individuals had the
requisite criminal mens rea and culpability to count as
“participants.” 9

   The district court’s assessment of the third element also
came up short. The court found that Martinez Vega’s
9
 Martinez Vega argues (Br. 71) that “participants” must have “the
same culpable mens rea” as their supervisor. Bapack holds
otherwise. 129 F.3d at 1325.
                                39
“activities were otherwise quite extensive in this area” of
“transport[ing] . . . narcotics and weaponry.” Sentencing Tr.
47. But the Guidelines’ “otherwise extensive” inquiry
pertains to the scope of the criminal activity as a whole, not
the defendant’s particular involvement in it. See U.S.S.G.
§ 3B1.1(b) (asking whether “the criminal activity involved
five or more participants or was otherwise extensive”)
(emphasis added). That is, the criminal activity must either
involve “five or more participants” or be “otherwise
extensive” in that it involves fewer than five criminally
culpable “participants,” but could include a number of
“unknowing outsiders.” United States v. Wilson, 240 F.3d 39,
49 (D.C. Cir. 2001) (“otherwise extensive” demands “a
showing that an activity is the functional equivalent of an
activity involving five or more participants”) (citation
omitted). On that point, the district court made no finding.

     Accordingly, we vacate Martinez Vega’s sentence and
remand to the district court for resentencing in view of the
legally required elements for a “manager or supervisor”
enhancement. In so doing, we reach no conclusion as to the
sufficiency of the existing record on those issues, but
emphasize that the review on remand is constrained to the
existing record. 10

                 III. Issues Raised by Cuevas

    Cuevas raises five arguments specific to the case against
him, namely, that the district court (i) should have granted

10
   Martinez Vega also asserts that he was eligible for a two-level
reduction as a “minor participant” under Section 3B1.2 of the
guidelines. The district court declined the decrease, finding
sufficient evidence that Martinez Vega played a significant role in
the conspiracy, Sentencing Tr. 45–46, and on this record we find no
error in that ruling.
                             40
Cuevas’s motion for a mistrial after Garrido testified about a
previously undisclosed conversation he had with Cuevas; (ii)
should not have admitted into evidence recordings of
Cuevas’s phone calls; (iii) violated the Confrontation Clause
by limiting Cueva’s questioning of cooperating witnesses; (iv)
wrongly permitted the exhibition of a video depicting a police
raid; and (v) erroneously applied sentencing enhancements for
being a manager or supervisor and for possession of a firearm.
None has merit.

     A. Garrido’s Reference to Cuevas as “Mincho”

     Throughout the trial, the Government alleged, and
Cuevas denied, that Cuevas was the FARC’s prominent
cocaine manufacturer known as “Mincho.” After two
witnesses had identified Cuevas as Mincho, the Government
called Garrido to testify about Cuevas’s extradition. The
following exchange occurred:

    Q: When did you first encounter Mincho, or the
    defendant Cuevas Cabrera that day?

    A: I went inside that area while he was being
    processed by the Colombian authorities. I went in. I
    asked, “Are you Mincho?” He said, “Yes.” I verified
    his name. Erminso Cuevas Cabrera.

Cuevas objected to the testimony on the ground that Cuevas’s
alleged statement to Garrido had not been disclosed during
discovery, and he requested that the testimony be stricken.
The court sustained the objection and issued the following
instruction to the jury:

    Ladies and gentlemen, Agent Garrido mentioned
    that when he spoke to Mr. [Cuevas] Cabrera, he
                              41
    asked him if he was Mincho, and he said, yes, I am
    Mincho. I am going to strike that testimony. That
    was not previously announced as evidence in the
    case about any statements that Mr. Cabrera may
    have made that he was Mincho. So I am going to
    strike that from the testimony, have you disregard
    that statement by—allegedly made by Mr. Cabrera.

     Cuevas nevertheless moved for a mistrial, which the
district court denied. Cuevas now argues the denial was error
because the testimony was highly prejudicial and because the
court’s curative instruction, by repeating the offending
testimony and by implying its exclusion was due only to a
technicality, exacerbated rather than mitigated the prejudice.

     A “mistrial is a severe remedy—a step to be avoided
whenever possible, and one to be taken only in circumstances
manifesting a necessity therefor.”            United States v.
McLendon, 378 F.3d 1109, 1112 (D.C. Cir. 2004). The
district court’s principal consideration in ruling upon a motion
for mistrial is the extent of prejudice suffered by the
defendant, and we review the district court’s denial only for
abuse of discretion. Id.

     In this case, it is not obvious why Garrido’s stricken
testimony was prejudicial considering that at least two other
witnesses previously had identified Cuevas as “Mincho,” and
the evidence established that “Mincho” is a common
nickname for Erminso. Further, whatever harm may have
been done by the testimony was promptly undone by Judge
Hogan’s curative instruction. “We normally presume that a
jury will follow an instruction to disregard inadmissible
evidence inadvertently presented to it, unless there is an
overwhelming probability that the jury will be unable to
follow the court’s instructions.” Greer v. Miller, 483 U.S.
                              42
756, 766 n.8 (1987) (internal quotation marks and citation
omitted). Neither Judge Hogan’s repetition of the offending
testimony (which was necessary to specify the objectionable
content for the jury after numerous intervening questions) nor
his stated reason (which was no more technical than any other
evidentiary ruling) created such an “overwhelming
probability” here.

           B. Admission of Cuevas’s Phone Calls

     In 2004 a federal judge in the Southern District of Florida
authorized telephone wiretaps based upon a DEA agent’s
affidavit stating that the “target telephones will be located
overseas” and that the “intercepts will be conducted from, and
monitored in, the Southern District of Florida.”               A
confidential DEA source then provided the monitored phones
to targets in Colombia. The Government intercepted Cuevas
discussing his operations on two calls, which it played at trial
during the testimony of the other party to the recorded calls.

     Cuevas argues the tapes were inadmissible because
federal law prohibits foreign surveillance and because the
federal judge who approved the wiretaps lacked jurisdiction to
do so. Cuevas forfeited these arguments by failing to raise
them in the district court, so we consider them at most for
plain error. United States v. Williams, 773 F.3d 98, 105 (D.C.
Cir. 2014); see also United States v. Burroughs, 810 F.3d 833,
837–38 (D.C. Cir. 2016).

     First, Cuevas’s contention that extraterritorial
surveillance is prohibited because “Title III . . . has no
extraterritorial   force”    reflects     a     fundamental
misunderstanding of the role of the statute. Title III of the
Omnibus Crime Control and Safe Streets Act of 1968
“imposes . . . limitations on the use of electronic
                               43
surveillance.” United States v. Chavez, 416 U.S. 580, 580
(1974).     If it does not apply extraterritorially, then
government surveillance outside the United States is
unconstrained, not forbidden, by Title III.

     Second, Cuevas’s contention that a “listening post” in the
Southern District of Florida was insufficient to confer
jurisdiction upon the federal court there is unavailing if only
because every circuit that has considered the question has
deemed a listening post sufficient. See, e.g., United States v.
Luong, 471 F.3d 1107, 1109 (9th Cir. 2006); United States v.
Rodriguez, 968 F.2d 130, 136 (2d Cir. 1992). With no
“controlling precedent” or “other absolutely clear legal norm”
to support Cuevas’s position, the purported error by the
district court, if error it be, cannot be deemed plain. See
United States v. Nwoye, 663 F.3d 460, 466 (D.C. Cir. 2011).

     C. Cross-Examination of Cooperating Witnesses

    At trial, former members of the FARC testified for the
Government. 11 Cuevas learned that these witnesses wore
monitoring devices on their ankles both for their own safety
and to prevent them from fleeing and illegally remaining in
the United States. Cuevas sought to cross-examine the
witnesses about the devices on the ground that they revealed
potential bias. After consulting with the U.S. Marshal
Service, the district court found the anklets were “a security
practice used with many witnesses,” and were not being used
because the witnesses were “under charges or otherwise
untrustworthy.” The court concluded that the devices had “no

11
  These witnesses were known as “reinsertados” because they had
been reintegrated into civil society through a Colombian
government program that grants members of the FARC immunity
for past crimes in exchange for cooperation with law enforcement.
                               44
relevance” to the witnesses’ credibility and that inquiry would
“lead into other areas . . . far afield from what is relevant in
this trial,” such as the threat Cuevas himself posed to safety of
the witnesses. Accordingly, the judge prohibited Cuevas from
cross-examining the witnesses about the devices.

    Cuevas argues the limitation violated the Confrontation
Clause of the Sixth Amendment to the Constitution of the
United States. Although that Clause guarantees a criminal
defendant “the right . . . to be confronted with the witnesses
against him,” a district judge has

    wide latitude insofar as the Confrontation Clause is
    concerned to impose reasonable limits on . . . cross-
    examination based on concerns about, among other
    things, harassment, prejudice, confusion of the
    issues, the witness’ safety, or interrogation that is
    repetitive or only marginally relevant.

Delaware v. Van Arsdall, 475 U.S. 673, 679 (1986). We
review the district court’s limitation of cross-examination for
abuse of discretion, with the central inquiry being “whether
the jury would have received a significantly different
impression of the witness’s credibility had defense counsel
been permitted to pursue the [disallowed] line of
questioning.” United States v. Wheeler, 753 F.3d 200, 205
(D.C. Cir. 2014).

     The district court did not abuse its discretion here.
Questions about the devices would be of no incremental value
to the defendant in this case, and the district court reasonably
concluded that such questions would “stray far afield from
what [was] relevant in this trial.” The jury was already aware
that all the former FARC members who testified were
admitted participants in a cocaine trafficking organization;
                              45
that several had admittedly engaged in guerilla warfare; that
some were admitted murderers; and that all had been spared
prosecution in return for their cooperation with law
enforcement. With all this laid bare, it is highly unlikely that
questions about the monitoring devices would have left the
jury with a “significantly different impression of the
witness’s” propensity to bias or motivation to lie on behalf of
the Government. Id.

                 D. Admission of the Video

     At trial, Lieutenant Colonel Alvarez Ochoa of the
Colombian National Police testified as an expert on
Colombian cocaine laboratories and the organization of the
FARC. Over Cuevas’s objection, the Government introduced
a video of a police raid, in which Alvarez participated, on a
cocaine laboratory unconnected to Cuevas. The video
depicted a typical cocaine lab in the jungle, the recovery of
seven tons of cocaine “base,” the demolition of the laboratory
with explosives, and helicopters that provided armed air
support. It is not clear from the testimony whether the video
depicted any violent resistance from the operators of the
laboratory, but Cuevas claims it did. Cuevas argues the video
of a raid on a cocaine lab outside either defendant’s territory
was irrelevant and highly prejudicial, and it should have been
excluded under Federal Rule of Evidence 403.

    Rule 403 permits exclusion of otherwise admissible
evidence if “its probative value is substantially outweighed by
a danger of . . . unfair prejudice, confusing the issues, [or]
misleading the jury.”        We review a district court’s
determination under Rule 403 “with great deference,
reversing only for grave abuse of discretion.” United States v.
Clarke, 24 F.3d 257, 265 (D.C. Cir. 1994). In this case,
Cuevas has failed even to offer any account of how the video
                              46
caused him any prejudice, let alone sufficient prejudice to say
the district court gravely abused its discretion.

               E. Sentencing Enhancements

     Cuevas raises the same objection to the three-level
“manager/supervisor” sentencing enhancement as does
Martinez Vega, namely that the district court erred in
applying the enhancement because there was insufficient
evidence of the culpability of anyone Cuevas supervised.
Unlike Martinez Vega, however, Cuevas was expressly found
by the district court to have supervised numerous culpable
individuals. We are bound by this factual finding unless it is
clearly erroneous, see United States v. Henry, 557 F.3d 642,
645 (D.C. Cir. 2009), which it is not. The evidentiary record
here, including Maria Santiago’s testimony that she worked
alongside 80 employees in a cocaine laboratory run by
Cuevas, supports the court’s finding.

     Cuevas also objects to the imposition of a two-level
enhancement, pursuant to U.S.S.G. § 2D1.1(b)(1), for
possession of a firearm during a drug offense. The district
court, however, expressly found that Cuevas carried a weapon
while running the lab, and this finding is far from clearly
erroneous. Two witnesses testified to having seen Cuevas
carry a handgun while committing drug offenses. Cuevas
challenges the credibility of those witnesses, but the “district
court’s credibility determinations are entitled to the greatest
deference from this court on appeal.” Carter v. Bennett, 840
F.2d 63, 67 (D.C. Cir. 1988). Cuevas gives us no basis for
disturbing the court’s finding.
                             47
                      IV. Conclusion

     We affirm the convictions of Juan Martinez Vega and
Erminso Cuevas Cabrera. We also affirm Cuevas’s sentence,
but we vacate Martinez Vega’s sentence and remand to the
district court for resentencing consistent with this opinion.

                                                 So Ordered
