 United States Court of Appeals
         FOR THE DISTRICT OF COLUMBIA CIRCUIT



Argued January 16, 2019             Decided August 20, 2019

                        No. 17-3018

                UNITED STATES OF AMERICA,
                        APPELLEE

                              v.

                   PHEERAYUTH BURDEN,
                       APPELLANT


                 Consolidated with 17-3019


        Appeals from the United States District Court
                for the District of Columbia
                   (No. 1:14-cr-00069-2)
                   (No. 1:14-cr-00069-3)


     Lindsay C. Harrison, pro bono, argued the cause and filed
the briefs for appellant. James Dawson entered an appearance.

    Daniel J. Lenerz, Assistant U.S. Attorney, argued the
cause for appellee. With him on the brief were Jessie K. Liu,
U.S. Attorney, and Elizabeth Trosman and Elizabeth H.
Danello, Assistant U.S. Attorneys.

    Before: HENDERSON, ROGERS and PILLARD, Circuit
Judges.
                               2
    Opinion for the Court filed by Circuit Judge PILLARD.

     Opinion concurring in part and concurring in the judgment
filed by Circuit Judge ROGERS.

     PILLARD, Circuit Judge: The Arms Export Control Act
(AECA) criminalizes exporting defense articles without a
license. 22 U.S.C. § 2778(b)(2), (c). Pheerayuth Burden, a
U.S.-resident Thai national who ran a business exporting goods
from the United States to Thailand, and his export business,
Wing-On LLC (collectively, the defendants), exported five
assault-rifle magazines and a grenade-launcher mount.
Following a three-week trial, a jury convicted the defendants
of conspiracy to violate the AECA, unlawful export in violation
of the AECA, and conspiracy to launder money.

     The defendants contend that three of the district court’s
rulings are reversible error. First, they argue that the court
erred in admitting video deposition testimony by a key witness
over a Confrontation Clause objection where the government
itself rendered the witness “unavailable” at trial by deporting
him shortly before trial without first making reasonable efforts
to arrange his return. Second, they challenge a jury instruction
defining the “willfulness” element of unlawful exportation of
defense articles as requiring only proof that the defendants
“acted with knowledge that the conduct was unlawful.” That
instruction was inadequate, they contend, because it failed to
tie the willfulness finding to the pertinent conduct and law,
creating an impermissible risk that the jury relied on evidence
that Burden thought he was violating Thai import law. Third,
defendants claim that the district court erred in admitting
Burden’s non-Mirandized statements because it failed to
account for his limited English abilities in determining that he
was not in custody when agents interrogated him.
                                3
     We hold that the district court erred in admitting the
deposition testimony because the government failed to make
reasonable efforts before it deported the witness to procure his
presence at trial. We conclude that the jury instruction was
correct as far as it went in instructing the jury to find that “the
defendant knew that his conduct was unlawful,” and that
“willfully” violating the law does not require proof “that a
defendant had read, was aware of, or had consulted the
licensing provisions of the Arms Export Control Act” as such.
Appellants’ Appendix (App.) 66. But we suggest clarification
of the willfulness instruction to more squarely require a finding
that defendants were aware of and knowingly violated their
legal obligation not to commit the charged actus reus. A case
such as this one—that includes evidence of consciousness of
guilt relating to distinct actus reus arguably violating different,
uncharged legal obligations—creates some risk of the jury
relying on evidence of consciousness of guilt unrelated to the
charged crime. We affirm the district court’s determination
that Burden was not in custody because, even assuming
language proficiency is relevant to the custody inquiry, a
reasonable officer would not have thought Burden’s imperfect
English meant a reasonable person in his position would have
believed himself detained during the interview.

     Because the error we identify was not harmless, we vacate
the judgments and remand for proceedings consistent with this
opinion.

                       BACKGROUND

     A. Legal Background

     The AECA establishes executive-branch control over the
export and import of “defense articles,” meaning arms or other
military items. See 22 U.S.C. § 2278. It authorizes the
                               4
President, “[i]n furtherance of world peace and the security and
foreign policy of the United States,” to control the export of
defense articles and services, designate which items count as
defense articles and services, and promulgate regulations for
those purposes. Id. § 2778(a)(1). The designated defense
articles make up the United States Munitions List (the
Munitions List or the List). Id. With certain enumerated
exceptions, “no defense articles or defense services designated
by the President” as part of the Munitions List “may be
exported or imported without a license for such export or
import, issued in accordance with” the AECA and its
associated regulations. Id. § 2778(b)(2). The State Department
is responsible for issuing licenses. See id.; 22 C.F.R. §§ 120.1,
120.20. The decision whether to issue an export license
implicates sensitive issues of national security and foreign
policy. It must “take into account whether the export of an
article would contribute to an arms race, aid in the development
of weapons of mass destruction, support international
terrorism, increase the possibility of outbreak or escalation of
conflict, or prejudice the development of . . . arms control or
nonproliferation agreements or other arrangements.” 22
U.S.C. § 2778(a)(2). The statute criminalizes “willfully
violat[ing] any provision of this section . . . or any rule or
regulation issued under this section.” Id. § 2278(c). It thus
criminalizes willfully exporting defense articles without a
license.

    The President delegated to the Secretary of State the
authority to designate defense articles and promulgate
regulations under the AECA, see Exec. Order No. 13637, 78
Fed. Reg. 16,129 (2013); 22 C.F.R. § 120.1(a), and the
Secretary accordingly promulgated the International Traffic in
Arms Regulations (ITAR), 22 C.F.R. §§ 120.1-130.17. The
ITAR prohibits exporting defense articles and services without
“obtaining the required license or other written approval” from
                               5
the appropriate office of the State Department. 22 C.F.R.
§ 127.1(a). The ITAR also includes the Munitions List, which
runs to over forty pages in the Code of Federal Regulations.
See id. § 121.1. The covered defense articles are described with
varying levels of specificity, such as “[r]iflescopes
manufactured to military specifications,” id. (Category I(f)),
“[g]uns over caliber .50,” id. (Category II(a)), “[i]ron powder
. . . with particle size of 3 micrometers or less produced by
reduction of iron oxide with hydrogen,” id. (Category
V(c)(4)(i)(B)), and “[h]elmets . . . providing a protection level
equal to or greater than NIJ Type IV,” id. (Category X(a)(6)).
The convictions in this case relate to items in Category I(h) of
the Munitions List: “Components, parts, accessories and
attachments” for the firearms listed in Category I(a)-(g). See
App. 89-90.

    B. Factual and Procedural Background

     Burden started Wing-On LLC (Wing-On), a freight-
forwarding business that shipped American goods to Thailand,
around 2008. In 2010, Kitibordee Yindeear-Rom became one
of Burden’s customers. A Thai national living in Thailand,
Yindeear-Rom had a business importing many different types
of goods from the United States to Thailand. As part of that
business, he helped his customers get gun parts and accessories
from the U.S. that they could not purchase directly because
U.S. companies would neither accept Thai credit cards nor ship
the parts to Thailand. According to Yindeear-Rom, Burden
initially ordered gun parts for him from U.S. vendors, received
them in the United States, then shipped them to Thailand.
Supplemental Appendix (S.A.) 291A-91B. Yindeear-Rom
later began placing the orders himself using a debit card
attached to a U.S. bank account Burden opened. S.A. 294-96,
479. Yindeear-Rom testified in his deposition that he
reimbursed Burden for the purchases he made on Burden’s
                              6
debit card by transferring money to Thai bank accounts
belonging to Burden and Burden’s associate. S.A. 298-300.
Neither Burden nor Wing-On had a license to export defense
articles on the Munitions List.

     In October 2013, Yindeear-Rom took a vacation to the
United States, where he was stopped and interviewed by
Department of Homeland Security (DHS) agents. He was
arrested two days later for conspiracy to violate American
export laws. He later pleaded guilty and was sentenced to
thirty-six months in prison. At Yindeear-Rom’s initial court
appearance, the DHS agents saw in the courtroom two people
they believed to be Burden’s wife and roommate, respectively.
Concerned that Burden might have been alerted to the
investigation, the agents went immediately to Wing-On’s
warehouse. Burden was not there, but the agents met one of
his employees, who helped the agents call him. They called
him again later that day and arranged an interview for that
evening at the warehouse.

     The DHS agents interviewed Burden in English without an
interpreter. They did not advise Burden of his rights with the
familiar warnings officials must give suspects in custodial
interrogation under Miranda v. Arizona, 384 U.S. 436, 444
(1966). At the beginning of the interview, one of the agents
gave the following preamble (recounted here with Burden’s
affirmative interjections omitted):

     We are federal agents for the U.S. Government so
     I have to let you know that you have to be honest
     with us[,] okay? If you don’t want to answer
     something, you don’t have to answer but you
     cannot lie to us. All right? And you can’t withhold
     relevant information. If you do, that is a crime.
                               7
     Okay? Punishable by up to five years in prison so
     just please be honest.

App. 174. The agent then asked, “Is your English good?” Id.
Burden replied, “A little bit.” App. 175. “If there’s anything
that I say that you don’t understand, ask me,” the agent said.
Id. “Okay,” Burden replied. Id. During the interview, Burden
admitted he had shipped gun parts to Yindeear-Rom and
falsified customs declarations. App. 266-71. The agents did
not arrest Burden at the end of the interview. S.A. 420-21. The
court’s eventual admission of Burden’s statement at his trial
over defense objections is the subject of his Miranda claim on
appeal. App. 429-33.

     Burden was arrested six months later, in May 2014. Trial
was initially scheduled for November 2015, but was continued
twice, first to April 2016 and then to September 2016. The
district court granted the second continuance because many
documents remained to be translated into English. The court
noted that the defense “can’t actually do this without translated
documents” and that “it’s not that [the defense has] been less
than diligent about it.” App. 381. That continuance introduced
a wrinkle into the trial, however: Yindeear-Rom was
scheduled to be released from prison in June 2016, three
months before the new trial date, and was to be deported after
his release. The government had a clear path to remove
Yindeear-Rom upon his release because he had stipulated when
he pleaded guilty to an order of removal that would “render[]
him permanently inadmissible to the United States,” which
assured that the government, “promptly upon his release from
confinement . . . may execute the order of removal according
to the applicable laws and regulations.” App. 47 (alteration in
original). The government in February 2016 moved to take
Yindeear-Rom’s deposition under Federal Rule of Criminal
Procedure 15, which governs depositions taken to preserve a
                               8
potential witness’s testimony for trial. S.A. 1; Fed. R. Crim. P.
15(a)(1). The district court granted the motion over the
defendants’ objections. The defense objected to the deposition
for some of the same reasons it asked for the second trial
postponement: the government had not produced sufficient
discovery to allow them to prepare for Yindeear-Rom’s
testimony. The court nonetheless allowed the deposition to be
taken to preserve evidence in the event that Yindeear-Rom
would be unavailable to testify. Yindeear-Rom’s videotaped,
in-court deposition took place over four days in March and
April. The court granted the government’s motion to reduce
Yindeear-Rom’s sentence in exchange for his testimony.

     The United States deported Yindeear-Rom to Thailand in
April 2016. Even though the government had substantial
bargaining leverage before it moved for his sentence reduction,
there is no record that it made any efforts before deporting him
to secure Yindeear-Rom’s presence at trial. It was only once
Yindeear-Rom was back in Thailand that the government
began to make such efforts.

     In seeking to bring Yindeear-Rom back a few months
later, the government contacted Yindeear-Rom’s counsel by
phone and mail. United States v. Burden, No. 14-cr-0069
(RMC), 2016 WL 5108010, at *3 (D.D.C. Sept. 20, 2016). Its
letter to counsel included a subpoena for Yindeear-Rom’s
testimony at trial and a promise to help him obtain a visa and
to pay his travel expenses, “including but not limited to round-
trip airfare, transportation, room, board, and per diem witness
fee.” Id. (quoting letter, S.A. 51). Yindeear-Rom’s lawyer
“forwarded the letter and subpoena to Mr. Yindeear-Rom in
Thailand, but was unable to confirm receipt or make any
representations about [his] willingness to testify.” Id. at *3.
The government also sent the letter and subpoena directly to
Yindeear-Rom’s last known email and physical address in
                               9
Thailand. Id. at *4. The government received no response to
either, but confirmed that the letter was signed for by “K. Yen,”
which it believed to be Yindeear-Rom. Id. DHS personnel in
Thailand eventually reached Yindeear-Rom by phone and
learned that he had received the email and letter, but that he
“had no desire to travel to the United States to cooperate in any
way.” Id. (quoting DHS Report of Investigation, S.A. 75).

     At trial, the court granted the government’s motion to
admit the Rule 15 deposition over the defendants’ objections.
Defendants argued that the government should have sought to
keep Yindeear-Rom in the country between his release from
prison and the trial. The court concluded that the witness was
unavailable, and that “the use of a videotaped deposition taken
in court, before the trial judge and including the presence of
Mr. Burden and cross examination by both defense lawyers,”
was “a very good substitute” for Yindeear-Rom’s live trial
testimony “that would allow the jury to observe his demeanor
and preserve the Defendants’ rights to confront witnesses
against them.” Id. at *3, *8.

     The government’s trial evidence included Burden’s
statement to DHS agents at the Wing-On warehouse that he
mislabeled customs declarations for shipments containing gun
parts, and packed gun parts hidden among other items for
shipping. App. 269-72. In his defense, Burden highlighted his
statements that he took those steps to evade Thai customs. He
told the agents that he concealed gun parts among other items
because “[y]ou want to hide from the custom in Thailand,”
App. 271, and that he falsified customs documents “[b]ecause
of tax in Thailand,” App. 281.

    The government, for its part, pointed to circumstantial
evidence tending to show that Burden had reason to know that
he was violating U.S. arms-export law. For instance, Burden
                                10
acknowledged in his statement to DHS agents that people
“[n]eed a license” to ship certain things, like gun parts. App.
203-04. Yindeear-Rom received a notice that a seized
shipment of gun parts violated the ITAR, see S.A. 212-13, and
even though he had ordered that shipment through a different
shipper (not Wing-On), Yindeear-Rom forwarded the notice to
Burden asking what he should do, see S.A. 282-83. Yindeear-
Rom then testified that the notice he forwarded informed both
of them of the requirements of the ITAR. S.A. 369. Burden
had also received a notice directly from U.S. Customs and
Border Protection that it had seized a rifle scope (controlled
under a distinct set of regulations analogous to the ITAR but
covering different items) because the scope could not be
exported without a license. See App. 171.

     Further evidence, however, suggested that Burden either
did not realize he was shipping real gun parts, or thought it was
legal under U.S. export law to ship those parts if they were to
be used with toy guns. As part of their business, the defendants
shipped BB guns (air guns that shoot small metal balls) and
Airsoft toys (which are similar to BB guns and shoot plastic
pellets). See App. 311-12, 574. Airsoft and BB guns
themselves may lawfully be exported without a State
Department license. The defense’s expert witness on firearms
and Airsoft identification testified that an Airsoft toy “looks
like a gun in every way, shape or form from the outside, same
length, weight, contour, field markings, but it won’t kill
anybody.” S.A. 672-73. They have all the same parts as the
real guns they mimic; in fact, real gun parts can be used with
Airsoft toys. App. 508-10; S.A. 676, 678. In his statement to
DHS agents, Burden said that his Thai customers were not
using gun parts “for the gun,” but “for the BB gun . . . for the
paintball [gun].” App. 259. A Wing-On manager testified that
employees were instructed not to ship parts for real guns but
that they could ship parts to “be used for toys for Airsoft items.”
                               11
App. 554-56, 574. Burden affirmed to one of his customers
that if a part was for a BB gun “then there’s no problem”
shipping it. App. 361. That evidence tended to support
Burden’s defense that he concealed the contents of shipments
to evade Thai customs law.

    Evidence also showed that Burden tried not to ship real
gun parts after realizing it was illegal. Burden sent an email to
Yindeear-Rom saying, “I have warned you many times that I
do not accept gun parts. . . . Stop sending them to me
absolutely!” App. 358. The Wing-On warehouse had a “no-
go” shelf for gun parts, where employees would segregate
items that they could not lawfully ship. See App. 350, 554-55.
There was ambiguous evidence suggesting that Wing-On may
have ultimately shipped some gun parts on the no-go shelf.

     The conflicting evidence regarding Burden’s intent
occasioned a dispute over the jury instruction defining
“willfully” under the AECA. The defendants proposed using
the Fifth Circuit pattern jury instruction, which requires the
jury to find that a defendant exported articles on the Munitions
List without obtaining a license from the Department of State;
and “[t]hat the defendant acted ‘willfully,’ that is, that the
defendant knew such license . . . was required for the export of
these articles and intended to violate the law by exporting them
without such license.” App. 99.

    Instead, the district court adopted the government’s
proposed instruction, which described the requisite state of
mind as follows:

     [A]n act is done willfully if it is committed with the
     knowledge that it was prohibited by law or was
     done in disregard of a known legal obligation. The
     government must prove that a defendant acted with
     knowledge that the conduct was unlawful. While
                             12
     the government must show that a defendant knew
     that the conduct was unlawful, it is not necessary
     for the Government to show that a defendant was
     aware of the specific law, rule, or regulation that
     the conduct may have violated.

     In other words, the government need not prove that
     a defendant had read, was aware of, or had
     consulted the licensing provisions of the Arms
     Export Control Act or the International Traffic in
     Arms Regulations, or the Munitions List. The
     government, however, must prove beyond a
     reasonable doubt, by reference to facts and
     circumstances surrounding the case, that a
     defendant knew that the conduct was unlawful.

App. 66; see App. 435-37.        The jury convicted the
defendants on all three counts—conspiracy to violate the
AECA, unlawful export in violation of the AECA, and
conspiracy to launder money. The defendants timely appealed
the district court’s admission of Yindeear-Rom’s deposition
and Burden’s statement to DHS, as well as the district court’s
jury instruction on the definition of “willfully.”

                        ANALYSIS

    A. Yindeear-Rom Was Not “Unavailable”                  for
       Purposes of the Confrontation Clause.

    We review legal conclusions regarding the Confrontation
Clause de novo, and reverse any error unless it was harmless
beyond a reasonable doubt. United States v. Moore, 651 F.3d
30, 69 (D.C. Cir. 2011) (citing constitutional harmless-error
standard in Chapman v. California, 386 U.S. 18, 24 (1967)).
Because the government concedes that, if it was error,
admitting Yindeear-Rom’s video deposition testimony instead
                               13
of producing him at trial was not harmless, we need only
consider the claimed error itself. See Appellee’s Br. 55 n.5.

     The Confrontation Clause of the Sixth Amendment
guarantees that, “[i]n all criminal prosecutions, the accused
shall enjoy the right . . . to be confronted with the witnesses
against him.” U.S. Const. amend. VI. Courts have long
recognized the critical importance of a criminal defendant’s
“opportunity to cross-examine and impeach a witness at trial
before the jury that will decide his innocence or guilt.” United
States v. Lynch, 499 F.2d 1011, 1022 (D.C. Cir. 1974). Live
witness testimony gives the jury the opportunity to assess the
witness’s demeanor and allows counsel to adjust examination
to other evidence and to the jury’s apparent reactions as the
witness testifies. “William Blackstone long ago recognized
this virtue of the right to confrontation, stressing that through
live testimony, ‘and this [procedure] only, the persons who are
to decide upon the evidence have an opportunity of observing
the quality, age, education, understanding, behavior, and
inclinations of the witness.’” United States v. Yida, 498 F.3d
945, 950 (9th Cir. 2007) (alteration in original) (quoting 3
William Blackstone, Commentaries on the Laws of England
373-74 (1768)).

    A testimonial statement by a person who does not appear
at trial may be admitted “only where the declarant is
unavailable, and only where the defendant has had a prior
opportunity to cross-examine.” Crawford v. Washington, 541
U.S. 36, 59 (2004); see also Fed. R. Evid. 804(b)(1).
Unavailability and prior opportunity to cross-examine are
independent criteria: Even when a defendant had a prior
opportunity to cross-examine the witness, if the government
does not establish that the witness is unavailable, the testimony
must be excluded. See id. at 57. Here, the parties agree that
defendants had an opportunity to cross-examine Yindeear-
                                 14
Rom during his videotaped deposition. The sole question is
whether he was “unavailable” for purposes of the
Confrontation Clause.

     Defendants argue that Yindeear-Rom was not truly
unavailable because the government procured Yindeear-Rom’s
unavailability by deporting him, and, in any case, it did not
make reasonable efforts before it deported him to ensure his
presence at trial. For its part, the government contends that
there is no per se presumption that the government fails the
Confrontation Clause’s test of good-faith and reasonable
efforts when it deports a witness, and that its reasonable, good-
faith efforts after it deported Yindeear-Rom sufficed.

     As a general matter, a witness is considered unavailable
only if the prosecution cannot procure her with good-faith,
reasonable efforts. See Ohio v. Roberts, 448 U.S. 56, 74
(1980), abrogated in part on other grounds by Crawford, 541
U.S. 36. It is the prosecution’s burden to establish that its
actions meet that test. Id. at 74-75. “The law does not require
the doing of a futile act” such as producing a witness who has
died, but “if there is a possibility, albeit remote, that affirmative
measures might produce the declarant, the obligation of good
faith may demand their effectuation.” Id. at 74. “The lengths
to which the prosecution must go to produce a witness . . . is a
question of reasonableness.” Id. (alteration in original)
(quoting California v. Green, 399 U.S. 149, 189 n.22 (1970)
(Harlan, J., concurring)). In Lynch, we held good-faith but
non-exhaustive efforts to find a witness were inadequate to
render her unavailable and justify admitting pretrial hearing
testimony. 499 F.2d at 1024. We treated the witness as
available because she was within the court’s jurisdiction and
the government had not “inquired at the local hospitals, area
police departments, the morgue, or of [the witness’s]
employer.” Id. In contrast, a witness whose “whereabouts
                               15
were entirely unknown,” who had been sent numerous
subpoenas at her parents’ house, was last heard from outside
the jurisdiction, and was unreachable by her family even in
case of an emergency was held in Ohio v. Roberts to be
unavailable even though, as Justice Brennan pointed out in
dissent, the government had not followed every possible lead
to find her. Compare 448 U.S. at 60-61, 75, with id. at 79-82
(Brennan, J., dissenting).

     When the government seeks to rely on prior recorded
statements of a witness on the ground that the witness is
unavailable, it bears the burden of establishing that its
unsuccessful efforts to procure the witness’s appearance at trial
were “as vigorous as that which the government would
undertake to [secure] a critical witness if it has no [prior]
testimony to rely upon in the event of ‘unavailability.’” Lynch,
499 F.2d at 1023; see also United States v. Mann, 590 F.2d 361,
367 (1st Cir. 1978). Where the government itself bears some
responsibility for the difficulty of procuring the witness, such
as by deporting the witness, the government will have to make
greater exertions to satisfy the standard of good-faith and
reasonable efforts than it would have if it had not played any
role. Failing to factor the government’s own contribution to
the witness’s absence into the Confrontation Clause analysis
would warp the government’s incentives. “This relatively high
good faith standard cannot be satisfied by perfunctory efforts,
if the rule is not to sanction the government’s procuring
depositions of witnesses, especially shaky witnesses, but then
discourage attempts to bring the witness to trial so long as the
government is satisfied with” the witness’s recorded testimony.
Mann, 590 F.2d at 367. Rather, the analysis of good-faith,
reasonable efforts should “include an assessment of the
government’s affirmative conduct” that allowed the witness to
become unavailable “in the first instance.” Yida, 498 F.3d at
955-56. That analysis should account for the good faith and
                              16
reasonableness of the government’s deportation of the witness
and of its attempts to secure witnesses it does deport.

     In a case such as this one, in which the government knew
or should have known of the potential need for the witness’s
testimony before he was deported, the government’s duty to
make good-faith, reasonable efforts to ensure the witness’s
presence arises before the witness leaves the United States.
Other courts that have addressed this question in the context of
witness deportation agree. In United States v. Tirado-Tirado,
the Fifth Circuit refused to deem unavailable a witness whom
the government had deported where the government “failed to
make any concrete arrangements with [the witness] prior to his
deportation,” and only shortly before trial made what the court
acknowledged were “fairly exhaustive” efforts to bring him
back from Mexico. 563 F.3d 117, 123, 125 (5th Cir. 2009).
The government had orally told the witness before deporting
him that his appearance would be required if the case went to
trial—a step not taken here—but the court faulted it for not
taking several other pre-deportation steps that might have
encouraged the witness to appear, including serving him with
a subpoena or other written notice. Id. at 123-24. In United
States v. Foster, the court followed Tirado-Tirado to exclude
videotaped depositions notwithstanding that the government
had advised the witnesses before deporting them that it might
need them to return, promised to allow their reentry and pay for
their travel, and collected contact information for them in
Mexico. 753 F. App’x 307, 309 (5th Cir. 2018). Emphasizing
the constitutional importance of taking “reasonable measures,
under the circumstances, that are likely to ensure that the
witness will return for trial,” the court declined to find the
unreachable witnesses “unavailable” because the government
had not verified their contact information from the outset,
sought alternative contact information, or remained in contact
                                17
with them over the months between their deportation and the
trial. Id. at 312.

     The Ninth Circuit in Yida similarly recognized “the
government’s obligation to use ‘reasonable means’ to ‘procure
the declarant’s testimony’ in the context of the government’s
affirmative role in a witness’s deportation,” 498 F.3d at 953,
and refused to admit testimony from a prior mistrial “when the
government itself share[d] some of the responsibility for its
inability to produce the witness at [the second] trial,” id. at 956.
The government’s efforts were insufficient where it had chosen
to detain the admittedly untrustworthy and skittish witness
prior to the first trial but, once it had that transcript in hand as
a substitute, deported the witness without considering the many
alternatives to confinement in federal prison that might have
prevented the witness’s absence. Id. at 959-60.

     The First Circuit, too, in Mann, excluded deposition
testimony of a crucial prosecution witness in lieu of live
testimony where, after the deposition, the government had
returned the witness’s passport and plane ticket that it had
seized upon her arrest. 590 F.2d at 366, 368. The court held
insufficient the government’s later offer to pay to bring the
witness back, similar to the government’s offer here. Id. at
363. “Implicit . . . in the duty to use reasonable means to
procure the presence of an absent witness is the duty to use
reasonable means to prevent a present witness from becoming
absent.” Id. at 368. Where the government fails to take
reasonable steps to prevent a witness from becoming absent,
the defendant should not suffer from the government’s choice.
See id.

    The cases on which the government relies are not to the
contrary. Foster distinguishes United States v. Allie, 978 F.2d
1401, 1403-08 (5th Cir. 1992), and United States v. Calderon-
                              18
Lopez, 268 F. App’x 279, 289 (5th Cir. 2008), on the basis of
extensive efforts the government made before it deported the
witnesses in those cases, none of which were made here.
Foster, 753 F. App’x at 311. And in United States v. Eufracio-
Torres, it was the defendant who initially opposed the
government’s motion to detain seven material witnesses
pending trial. 890 F.2d 266, 268 (10th Cir. 1989). The court
thought it significant that none of those witnesses had been
charged with any crime, yet they were detained while
defendant Eufracio-Torres was free on bond. Id. Eufracio-
Torres changed his position to request their detention pending
trial only after their depositions were taken—a request the
court denied. Id. When the witnesses could not be brought
back for trial and the government sought to use the depositions,
the court held that the government’s good-faith, reasonable
efforts supported its request: Before they left the country, the
government had given the witnesses subpoenas, instructions
for reentry, travel reimbursement, appearance fees, and
obtained their promises to return to testify. Id. No such steps
were taken here. The government’s reliance on United States
v. Rivera is similarly misplaced. 859 F.2d 1204, 1207-09 (4th
Cir. 1988) (witnesses but not defendant were being detained,
and court found no prejudice claimed or suffered from use of
witness depositions taken at the witnesses’ own request before
they were released and voluntarily left the United States).

     Under the applicable standard, the government failed to
show that Yindeear-Rom was “unavailable” for purposes of the
Confrontation Clause. The government’s efforts to secure his
presence at trial did not begin until after he was deported. See
Burden, 2016 WL 5108010, at *3-4. Before his deportation,
the government did not give Yindeear-Rom a subpoena, offer
to permit and pay for him either to remain in the U.S. or to
return here from Thailand, obtain his commitment to appear,
confirm his contact information, or take any other measures.
                               19
See id. at *9. Its only efforts began once he was out of custody,
out of the jurisdiction, and no longer dependent on the
government’s good graces for lenient treatment. Yindeear-
Rom’s eagerness to return to Thailand helped to persuade the
district court that further efforts to persuade him to testify at
trial would have been futile. See id. But in these circumstances
that eagerness cuts the other way. Given the government’s
duty to make good-faith, reasonable efforts before Yindeear-
Rom’s deportation, “a witness’s known reluctance to testify
adds to the government’s burden to show that it made
‘reasonable, good faith efforts’ to secure her appearance
because it makes her failure to appear voluntarily all the more
foreseeable.” Brooks v. United States, 39 A.3d 873, 886 (D.C.
2012). This is a case where the “possibility, albeit remote, that
affirmative measures might produce the declarant . . .
demand[ed] their effectuation.” Roberts, 448 U.S. at 74. Any
chance the government had of securing Yindeear-Rom’s
appearance at trial would have been far greater had it addressed
the problem as soon as it knew it would rely on his testimony.
Instead, its own approach appears to have ensured the futility
of the post-deportation efforts.

     We recognize that it may not always be reasonable to
expect the government to postpone removal until trial—
particularly if the government would have to detain the witness
in order to keep her in the country. See Aguilar-Ayala v. Ruiz,
973 F.2d 411, 419 (5th Cir. 1992) (enjoining Department of
Justice policy of automatically detaining undocumented
immigrant material witnesses because “undocumented aliens
have an overriding liberty interest in not being detained as
material witnesses”). And we assume that “in some cases the
need for the criminal defendant to confront the witness at trial
(rather than at deposition) might outweigh the material witness’
liberty interest in being released immediately,” whereas in
other cases it will not. Id. (emphasis omitted). In order to
                               20
identify the existence and extent of any such conflict, however,
the unavailability inquiry must account for whether the
government has addressed potentially reasonable means of
securing removable witnesses’ live testimony short of
detention, such as placing them in “lesser custody,” “supplying
maintenance, and retaining [their] passport[s] and ticket[s],”
and “plac[ing] [them] under subpoena.” Mann, 590 F.2d at
366; see also Allie, 978 F.2d at 1407 (holding that the
government’s efforts were reasonable where it offered
witnesses work permits to keep them in the United States).

     Because the government’s omissions place its efforts
below the standard the Confrontation Clause demands, we need
not decide precisely how the government should have sought
to prevent the witness from becoming unavailable. While the
government’s deportation of a witness may sometimes fail the
standard of good-faith and reasonable efforts, we reject any per
se rule that no witness the government deports can be
considered unavailable under the Confrontation Clause.
Consistent with the fact-intensive nature of the standard, the
government decries any per se rule, see Appellee’s Br. at 45-
46, the defendants do not advocate one, see Appellants’ Reply
Br. 24 n.12, and no circuit has adopted any such categorical
approach.

     We hold that the duty to use reasonable means to procure
a witness’s presence at trial includes the duty to use reasonable
efforts to prevent a witness from becoming absent in the first
place. The government does not dispute that it made no efforts
before deporting Yindeear-Rom to secure his presence at trial.
The witness thus was not “unavailable” such that prior
testimony could be admitted consistent with the Confrontation
Clause. Because admitting his deposition was not harmless
beyond a reasonable doubt, we vacate the convictions and
remand for a new trial.
                              21
   B. Guidance Regarding the             Jury    Instruction’s
      Definition of “Willfully”

    Although our resolution of the Confrontation Clause issue
is sufficient to dispose of this appeal, we provide some
guidance regarding the jury instruction’s definition of the term
“willfully,” an issue that was fully briefed and argued.

     The parties agree that defendants “willfully” violate the
AECA only where they act with knowledge that their conduct
is unlawful. The Supreme Court has explained that “willfully”
is “a word of many meanings whose construction is often
dependent on the context in which it appears.” Bryan v. United
States, 524 U.S. 184, 191 (1998) (internal quotation marks
omitted). “As a general matter, when used in the criminal
context, a ‘willful’ act is one undertaken with a bad purpose.
In other words, in order to establish a ‘willful’ violation of a
statute, the Government must prove that the defendant acted
with knowledge that his conduct was unlawful.” Id. at 191-92
(internal quotation marks omitted). The parties disagree about
how specific that knowledge must be under the AECA’s
willfulness standard.

     Defendants argue that the AECA’s prohibition on
“willfully violat[ing] any provision of this section,” 22 U.S.C.
§ 2778(c), means that they should not have been convicted
unless they “were aware of the specific law, rule, or regulation
that the[ir] conduct may have violated.” Appellants’ Br. 17
(alteration in original). Before us, they frame this standard as
“requir[ing] the government to prove an individual was aware
the items he exported were on the [Munitions List],” id. at 18-
19, though their requested jury instruction would instead have
demanded proof that they knew that there was a license
requirement for their exports, App. 99. The heart of
defendants’ case at trial was that they “had not willfully
                               22
violated [the] AECA because they believed the parts were
intended for use in Airsoft BB guns, not real guns, and they
believed such parts could be exported without a license.”
Appellants’ Br. 12. Under the court’s jury instructions, they
contend, “intent to violate Thai customs duties or Thai gun
control laws could support the jury’s finding of willfulness.”
Id. at 31. The government defends the district court’s
instruction on the ground that “the AECA is not one of the
extremely rare, highly technical statutes that the Supreme
Court has found to require a heightened willfulness showing,”
so the government did not have to prove defendants had
knowledge of the license requirement or the Munitions List as
such. Appellee Br. 16.

     As discussed below, because it was ambiguous as to what
“conduct” defendants had to know was “unlawful,” the district
court’s jury instruction arguably fell short of the baseline
requirement that the mens rea relate to the charged actus reus.
But we believe that the district court correctly instructed that,
if defendants knew exporting the charged items without a
license was unlawful, they did not need specific knowledge of
the Munitions List. Thus, the district court was right that “the
government need not prove that a defendant had read, was
aware of, or had consulted the licensing provisions of the Arms
Export Control Act or the International Traffic in Arms
Regulations, or the Munitions List.” App. 66. For purposes of
the AECA, a requirement of proof that defendants knew the
proscribed conduct was unlawful adequately protects against
“the danger of ensnaring individuals engaged in apparently
innocent conduct.” Bryan, 524 U.S. at 194.

    Most criminal prohibitions require only proof that the
crime was committed “knowingly,” meaning that the defendant
knew of the facts that made his act illegal, even if he did not
know the act was illegal. When Congress wants to ensure that
                              23
defendants will be convicted only if they have a more culpable
state of mind, it limits the crime to conduct that a defendant
engages in “willfully.” See id. at 191-92. The Court has
developed an approach to “willfulness” that is calibrated to the
statutes in which it appears, consistently reading it to require
proof that the defendant had a sufficiently culpable state of
mind, but not to require proof so specific as to stymie the
statute’s enforcement. It has required proof that a defendant
know which law he was breaking in only two contexts:
criminal tax evasion, and currency structuring.

     In Cheek v. United States, a tax case, the Court explained
Congress’s inclusion of a willfulness requirement for felony
tax-evasion as resting partly on the recognition that “[t]he
proliferation of statutes and regulations has sometimes made it
difficult for the average citizen to know and comprehend the
extent of the duties and obligations imposed by the tax laws.”
498 U.S. 192, 199-200 (1991). The Court held that the
willfulness requirement could be defeated by the defendant’s
good-faith belief that he “was not a person required to file a
return or to pay income taxes and that wages are not taxable
income,” even if that belief was unreasonable. Id. at 203.

     In Ratzlaf v. United States, the Court interpreted
“willfully” in the context of a statute criminalizing “currency
structuring.” 510 U.S. 135, 136, 144 (1994). The anti-
structuring law prohibited a customer from breaking up a large
financial transaction into multiple smaller ones to avoid
triggering a bank’s legal duty to report transactions over
$10,000. Id. at 145. The Court held that “willfulness” meant
that the defendant had to be aware not only of reporting
obligations applicable to banks, but of his own distinct
obligation not to structure his transactions for the purpose of
avoiding triggering the bank’s obligation to report. Id. at 137-
38. In other words, “[t]o convict Ratzlaf of the crime with
                              24
which he was charged . . . the jury had to find he knew the
structuring in which he was engaged was unlawful.” Id. at 149.

     In Bryan, which concerned unlicensed firearms-dealing,
the Court concluded that “requiring only knowledge that the
conduct is unlawful [was] fully consistent” with Congress’s
purpose in adding a willfulness requirement to the firearms
statute “to protect law-abiding citizens who might
inadvertently violate the law.” 524 U.S. at 195 n.23. Bryan
distinguished the firearms law before it from the “highly
technical” statutes at issue in Cheek and Ratzlaf, which had
justified “‘carv[ing] out an exception to the traditional rule’
that ignorance of the law is no excuse and requir[ing] that the
defendant have knowledge of the law”—that is, the specific
law he violated. Bryan, 524 U.S. at 194-95 (quoting Cheek,
498 U.S. at 200).

     Following Bryan, most courts of appeals to consider the
issue have interpreted the AECA’s requirement that a violation
be “willful” not to require specific awareness of the Munitions
List as such. What they have required—as we do here—is
proof that defendants knew it was illegal to export the items
they shipped without a license. See United States v. Henry, 888
F.3d 589, 598-600 (2d Cir. 2018) (“[W]illfulness requires only
that the defendant know that what he was doing was illegal,
and not that he know that his conduct was prohibited under a
specific AECA provision or related regulation.”); United States
v. Bishop, 740 F.3d 927, 932-33 (4th Cir. 2014) (government
need not show defendant knew “that the ammunition was
specifically covered by the AECA,” but only that he had
“general knowledge of an export’s illegality”); United States v.
Chi Mak, 683 F.3d 1126, 1138 (9th Cir. 2012) (affirming
instruction that conviction did not require proof that “the
defendant had read, was aware of, or had consulted the specific
regulations governing his activities”); United States v. Roth,
                               25
628 F.3d 827, 835 (6th Cir. 2011) (the AECA “does not require
a defendant to know that the items being exported are on the
Munitions List,” but only “knowledge that the underlying
action is unlawful”); United States v. Tsai, 954 F.2d 155, 160-
62 & n.3 (3d Cir. 1992) (jury need not find that defendant
“knew all of the specifics of the law,” but “what it had to find
was that that the defendant knew that he could not export that
particular item”); United States v. Murphy, 852 F.2d 1, 6-7 (1st
Cir. 1988) (requiring proof that “defendant must know that his
conduct in exporting from the United States articles proscribed
by the statute is violative of the law,” but rejecting requirement
that he must know specifically that the article was on the
Munitions List or that there was a licensing requirement).

     The Eleventh Circuit in United States v. Wenxia Man
characterized the willfulness requirement of the AECA as more
demanding than that of the statute in Bryan, but its bottom line
is not materially different from that of the other circuits. See
891 F.3d 1253, 1268 (11th Cir. 2018). That court hewed to its
pre-Bryan precedent that “aware[ness] of the generally
unlawful nature of [one’s] actions is insufficient,” but was
satisfied with proof “that a conspirator actually knew that it was
unlawful to export the [items] and intentionally violated [the]
known legal duty not to export [them].” Id. (internal quotation
marks omitted) (alterations in original) (quoting United States
v. Adames, 878 F.2d 1374, 1377 (11th Cir. 1989)). The Fifth
Circuit held in United States v. Hernandez that the AECA
demands a finding that the defendant “knew he was unlawfully
exporting weapons on the Munitions List,” but that case
predated Bryan, Cheek, and Ratzlaf. 662 F.2d 289, 292 (5th
Cir. 1981). The Seventh Circuit did so more recently, but it,
too, took no account of those Supreme Court cases. See United
States v. Dobek, 789 F.3d 698, 700 (7th Cir. 2015).
                               26
     We hold that the district court’s jury instruction was
correct insofar as it rejected defendants’ position that the
willfulness requirement in the AECA is akin to those at issue
in Cheek and Ratzlaf, and clarified that the government need
not prove defendants knew the specific law their conduct
violated.

     That does not quite resolve the issue, however, because of
ambiguity in the meaning of “conduct” in the instruction that a
willful violation of the AECA requires that the defendant
“acted with knowledge that his conduct was unlawful.” App.
66. More is required where, as here, there is evidence of
willfully unlawful conduct apart from the charged offenses,
creating a risk that the jury may consider any and all evidence
of the defendant’s guilty mind—whatever its object—as
supporting willful commission of the charged offense. The
willfulness instruction arguably fell short in not specifying that
the unlawful “conduct” the jury must find the defendants to
have willfully done was the actus reus that violated the AECA:
unlawfully exporting the magazines and mount without a
license. To be sure, the rest of the instruction made clear that
the actus reus of the charged offense was exporting the items
without a license, and we review jury instructions as a whole.
United States v. McGill, 815 F.3d 846, 888 (D.C. Cir. 2016).
But we nonetheless detect a potential problem specific to the
instruction’s discussion of willfulness—an issue that is both of
central importance and easily muddied. It is natural enough
that jurors who are told they may convict upon finding the
defendants did the requisite act, so long as the defendant had a
guilty mind, may not parse the object of the guilty mind. To
prompt that important precision, the instruction’s definition of
“willfully”—the word at issue here—should specify that the
actus reus was the only “conduct” to which defendants’ guilty
mental state could apply for a finding of willfulness.
                               27
     The requirement that the mens rea relate to the charged
actus reus is the baseline for any criminal mental standard. See
Dixon v. United States, 548 U.S. 1, 6 (2006) (“[C]riminal
liability is normally based upon the concurrence of two factors,
an evil-meaning mind [and] an evil-doing hand.” (second
alteration in original) (internal quotation marks omitted)). If a
statute requires that the defendant knowingly perform the act
that violates the law—even where he need not also know that
the act is illegal—then he must knowingly perform the charged
actus reus, not some other, uncharged act. See Bryan, 524 U.S.
at 193 (“[T]he term ‘knowingly’ merely requires proof of
knowledge of the facts that constitute the offense.” (emphasis
added)). So, too, with willfulness. The district court and the
parties agree that willfulness requires that the defendant “acted
with knowledge that his conduct was unlawful.” App. 66; see
Bryan, 524 U.S. at 193. The conduct that he must know was
unlawful is the actus reus of the crime with which he is
charged.

     Because the willfulness instruction required only that the
defendants acted with knowledge that “the conduct” was
unlawful, App. 66, there is some chance that the jury convicted
based in part on defendants’ evasiveness in importing to
Thailand. On retrial, the instruction should make clear that an
AECA conviction requires that defendants knew of the
unlawfulness of the charged unlicensed export of the items
from the United States, and that a willfulness finding cannot
draw on evidence that they knew the related, but legally and
factually distinct, import of those items into Thailand was
illegal.
                              28
   C. Burden’s Limited English Did Not Render His
      Interrogation Custodial for Miranda Purposes.

    We review de novo the determination whether Burden was
in custody and thus entitled to Miranda warnings before any
interrogation, and we review the underlying factual findings for
clear error. United States v. Hallford, 756 F. App’x 1, 5 (D.C.
Cir. 2018). If the court erroneously admits a non-Mirandized
statement, we must reverse unless the admission was harmless
beyond a reasonable doubt. United States v. Brinson-Scott, 714
F.3d 616, 622 (D.C. Cir. 2013).

     In Miranda, the Court held that “the prosecution may not
use statements, whether exculpatory or inculpatory, stemming
from custodial interrogation of the defendant unless it
demonstrates the use of procedural safeguards effective to
secure the privilege against self-incrimination.” 384 U.S. at
444. Defendants argue that Burden’s limited English abilities
rendered the interview “custodial.” We disagree. We see no
error in the district court’s admission of Burden’s non-
Mirandized statement because Burden was not in custody when
the agents questioned him at his warehouse. His English
proficiency was not an “objective circumstance surrounding
the interrogation” that a reasonable officer would have
assumed bore on whether Burden felt free to leave the
interview.

     Miranda warnings are required as a bulwark against the
coercive power of being taken into police custody and
interrogated. “An individual swept from familiar surroundings
into police custody, surrounded by antagonistic forces, and
subjected to . . . techniques of persuasion . . . cannot be
otherwise than under compulsion to speak.” Miranda, 384
U.S. at 461. Police custody is sometimes self-evident, as in
Miranda’s own case: The police arrested him and took him to
                               29
a police station interrogation room where they questioned him.
Id. at 491. But a person is also in custody when he is
“otherwise deprived of his freedom of action in any significant
way.” Id. at 444. In “Miranda case law, ‘custody’ is a term of
art that specifies circumstances that are thought generally to
present a serious danger of coercion.” Howes v. Fields, 565
U.S. 499, 508 (2012).

     The Supreme Court has laid out guidelines for the custody
analysis. “In determining whether a person is in custody,”
triggering the duty to give Miranda warnings,

     the initial step is to ascertain whether, in light of
     the objective circumstances of the interrogation, a
     reasonable person [would] have felt he or she was
     not at liberty to terminate the interrogation and
     leave. And in order to determine how a suspect
     would have gauge[d] his freedom of movement,
     courts must examine all of the circumstances
     surrounding the interrogation. Relevant factors
     include the location of the questioning, its duration,
     statements made during the interview, the presence
     or absence of physical restraints during the
     questioning, and the release of the interviewee at
     the end of the questioning.

Id. at 509 (alterations in original) (internal quotation marks and
citations omitted).

     “[W]hether a suspect is ‘in custody’ is an objective
inquiry.” J.D.B. v. North Carolina, 564 U.S. 261, 270 (2011).
That means that, while the analysis accounts for “any
circumstance that would have affected how a reasonable person
in the suspect’s position would perceive his or her freedom to
leave,” it “involves no consideration of the actual mindset of
the particular suspect subjected to police questioning.” Id. at
                               30
271 (internal quotation marks omitted). The benefit of the
objective test is practical: It “avoids burdening police with the
task of anticipating the idiosyncrasies of every individual
suspect and divining how those particular traits affect each
person’s subjective state of mind.” Id.

     The test, while objective, is also contextual. Because all
of the “objective circumstances of the interrogation” must be
considered, Howes, 565 U.S. at 508, individual characteristics
that have an “objectively discernible relationship to a
reasonable person’s understanding of his freedom of action,”
such as a child suspect’s age, J.D.B., 564 U.S. at 275, must be
taken into account. Under circumstances in which “a
reasonable child subjected to police questioning will . . . feel
pressured to submit when a reasonable adult would feel free to
go[,] . . . courts can account for that reality without doing any
damage to the objective nature of the custody analysis.” Id. at
272. That is because age “generates commonsense conclusions
about behavior and perception” that “apply broadly to children
as a class.” Id. A reasonable eight-year-old will not necessarily
feel free to leave when a reasonable adult would.

     Because the test is designed to guide police, a person’s
youth—or analogous circumstances bearing on a reasonable
person’s perception of her freedom to leave—only factors into
the custody analysis where it “was known to the officer at the
time of the interview, or would have been objectively apparent
to any reasonable officer.” Id. at 274. The test thus includes a
double inquiry: whether it would have been apparent to a
reasonable officer that a reasonable person in the suspect’s
position would not have felt free to leave. In holding that the
suspect’s youth was an objective circumstance relevant to the
custody analysis, the Supreme Court suggested that other
personal characteristics, like blindness, could be similarly
relevant. Id. at 278. The Court underscored: “Not once have
                              31
we excluded from the custody analysis a circumstance that we
determined was relevant and objective, simply to make the
fault line between custodial and noncustodial ‘brighter.’” Id.
at 280.

     Under some circumstances, English language capabilities
might have an “objectively discernible relationship to a
reasonable person’s understanding of his freedom of action”
that would bear on the custody analysis for purposes of
Miranda. Id. at 275. Some courts have accordingly factored
limited English abilities into the custody inquiry. The Eighth
Circuit explained that “the ultimate issue is whether a
reasonable police officer conducting [an] otherwise non-
custodial interview would have given Miranda warnings
because he realized that the questioning would be perceived by
[the defendant] as custodial due to his limited English language
skills.” Thatsaphone v. Weber, 137 F.3d 1041, 1045 (8th Cir.
1998). In United States v. Kim, the Ninth Circuit weighed
limited English proficiency (among other factors the court
deemed important) because, under the circumstances, it bore
on the defendant’s ability to understand whether she was a
criminal suspect. 292 F.3d 969, 977 (9th Cir. 2002). Kim had
arrived at the store her family owned to find many police cars
outside and the door locked; the police let her, but not her
husband, enter, locked the door, did not let her son (who was
already inside) speak to her, and forced her to speak only
English, though she and her son informed the officers that she
did not speak English well. Id. at 971-72. The court held that
Kim’s interrogation was custodial partly because the police
“temporarily took over complete control of Kim’s store,
creating ‘a police-dominated atmosphere,’ in which the police
kept Kim physically isolated from two family members who
could have provided both moral support and, given her limited
English, a more complete understanding of the overall
situation.” Id. at 977. Both Thatsaphone and Kim preceded the
                               32
Court’s application of the custody analysis to a child in J.D.B.,
but both decisions comport with J.D.B. insofar as they consider
whether a reasonable officer would have been able to discern
that the language limitations of a reasonable person in the
suspect’s position would have contributed to that person’s not
feeling free to leave. Since J.D.B., at least one other court has
held a suspect’s limited English proficiency relevant to
J.D.B.’s objective inquiry. See United States v. Han, 199 F.
Supp. 3d 38, 52-54 (D.D.C. 2016).

     The district court in this case correctly held that a
reasonable officer would not have thought that Burden’s
language abilities prevented him from feeling free to leave, and
thus properly admitted Burden’s non-Mirandized statement.
Even though Burden sometimes had trouble formulating
responses and appeared to lack perfect comprehension of all
the questions, the evidence does not suggest that it would have
been apparent to a reasonable officer that Burden was not
understanding what was being said.

     The defendants identify only one moment, when the DHS
officer was explaining the purpose and terms of the interview,
when they believe that a reasonable officer should have
recognized that Burden’s English skills would affect the
perception of a reasonable person in his position as to whether
he was free to leave:

     UNIDENTIFIED AGENT NO. 1: We are federal
     agents for the U.S. Government so I have to let you
     know that you have to be honest with us —

     PHEERAYUTH BURDEN: Uh-huh.

     UNIDENTIFIED AGENT NO. 1: — okay? If you
     don’t want to answer something, you don’t have to
     answer but you cannot lie to us.
                              33
     PHEERAYUTH BURDEN: Okay.

     UNIDENTIFIED AGENT NO. 1: All right? And
     you can’t withhold relevant information.

     PHEERAYUTH BURDEN: Uh-huh.

     UNIDENTIFIED AGENT NO. 1: If you do, that is
     a crime.

     PHEERAYUTH BURDEN: Okay

     UNIDENTIFIED AGENT NO. 1: Okay?
     Punishable by up to five years in prison so just
     please be honest.

     PHEERAYUTH BURDEN: Yeah.

App. 174. While the agent’s statement was somewhat
confusing, it is not clear from this exchange that Burden was
not comprehending what the agent was saying to him or
somehow believed he could not leave an interview at his own
warehouse that he had agreed to by phone and shown up for of
his own accord.

     The district court did not refuse to consider Burden’s
proficiency entirely, as defendants assert. It properly applied
the custody test by evaluating how a reasonable officer would
have perceived Burden’s comprehension. It noted “that for
each of the points that the Special Agent was communicating
to Mr. Burden, Mr. Burden said okay or yes or [uh-huh],
reflect[ing] responses like that which would give one
reasonably the understanding that Mr. Burden understood what
was being said.” App. 430-31.
                                34
     The custody question was not otherwise close. The district
court found that Burden “arrived with his wife at his own work
place, at the time that he had set and there was no evident effort
to overcome his will. There was no effort to put him in
handcuffs, no threats, other threats during the course of the
interview.” App. 431. Burden himself “chose where he was
going to sit, he chose the room in which they were going to
talk,” and he “showed that he knew he could get up, go out,
open the door and talk to somebody outside throughout the
course of this.” App. 432. One of the two agents who
questioned Burden testified that Burden had chosen where and
when the interview would take place, S.A. 400, and that the
agents wore plainclothes and did not display their badges or
weapons, S.A. 407. The interview lasted no more than three
hours and Burden left when it was over. In sum, “the location
of the questioning, its duration, statements made during the
interview, the presence or absence of physical restraints during
the questioning, . . . the release of the interviewee at the end of
the questioning,” and other factors all support the conclusion
that Burden was not in custody. Howes, 565 U.S. at 509
(internal quotation marks and citations omitted). Because
Burden’s imperfect English would not have given a reasonable
officer the impression that a reasonable person in Burden’s
position would have believed himself detained, it does not
change that determination here.

                           *    *    *

     For the foregoing reasons, we affirm the district court’s
admission of Burden’s non-Mirandized statement to DHS
agents. We nonetheless vacate the convictions in view of the
error in the admission of Yindeear-Rom’s deposition
testimony.

                                                      So ordered.
     ROGERS, Circuit Judge, concurring in part, and concurring
in the judgments: I join the court in reversing the judgments of
conviction and remanding the case for a new trial because the
district court erred in admitting at trial the deposition of a key
government witness taken pursuant to Federal Rule of Criminal
Procedure 15. See Op. 12–21. As the proponent of the prior
testimony, the government had the burden of establishing
Yindeear-Rom’s unavailability by making reasonable efforts to
procure his presence at trial, see United States v. Lynch, 499
F.2d 1011, 1022 (D.C. Cir. 1974); FED. R. EVID. 804(a)(5)(A),
and failed to offer evidence that it did so. See Op. 15–17. The
district court’s error violated defendants’ Confrontation rights
under the Sixth Amendment to the Constitution. See Ohio v.
Roberts, 448 U.S. 56, 74 (1980), abrogated on other grounds
by Crawford v. Washington, 541 U.S. 36 (2004). The
government concedes that if there was error, it was not
harmless beyond a reasonable doubt. Appellee’s Br. 55 n.5.

     In view of our remand for a new trial, see United States v.
Hite, 769 F.3d 1154, 1167 (D.C. Cir. 2014), I also join two of
the court’s other conclusions. First, I agree the district court
did not err in denying defendant Pheerayuth Burden’s motion
to suppress statements that he had made during an interview
with Department of Homeland Security agents at Burden’s
suggestion at his warehouse, while his wife was present. Op.
28–34. The district court could reasonably conclude that,
under the circumstances, it would not have been “objectively
apparent to any reasonable officer,” J.D.B. v. North Carolina,
564 U.S. 261, 274 (2011), that Burden’s lack of fluency in the
English language would have prevented him from
understanding that he was not detained at the time.

     Second, I agree the district court did not err in rejecting the
defendants’ requested jury instruction on the meaning of
“willfully” under the Arms Export Control Act (“AECA”). See
Op. 21–26. This court now joins the majority of circuit courts
of appeal to have considered the issue that the AECA does not
                                2
require the government to prove that defendants know the
specific items they exported were on the Munitions List.

     But I cannot agree that the instruction on “Willful
Violation of Arms Export Control Act” (“AECA instruction”),
App. 66, failed adequately to define “the conduct” that the jury
had to find was “willfully” committed by the defendants. Op.
26–27. When reviewing an instruction for legal error, the
“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. Vega, 826 F.3d 514,
524 (D.C. Cir. 2016) (quoting United States v. Wilson, 605 F.3d
985, 1018 (D.C. Cir. 2010)). Courts must “consider not just
the challenged phrases, but the instruction as a whole.” United
States v. Washington, 106 F.3d 983, 997 (D.C. Cir. 1997)
(quoting United States v. Merlos, 984 F.2d 1239, 1242 (D.C.
Cir. 1993)).

      The district court instructed the jury that “[t]hrough the
Arms Export Control Act and the International Traffic in Arms
Regulations, Congress and the President have made it a
criminal offense for anyone willfully to export or attempt to
export from the United States any defense article without first
obtaining a license or written approval from the U.S.
Department of State.” App. 66 (emphasis added). In the next
sentence, the court instructed that “[t]he defendants are charged
. . . with specific instances of willfully exporting United States
Munitions List items . . . in violation of the export control
laws.” Id. (emphasis added). Adding specific details about the
alleged unlawful conduct, the district court instructed the jury
that Count 2 of the superseding indictment charged the
defendants with exporting, in violation of the AECA, two types
of items on the U.S. Munitions List: “(1) five AR Style, NATO
5.56, 30 round magazines, and (2) a KAC-Knight Armament
                                3
M203 Qd Mount.” Id. Regarding the word “willfully,” the
district court instructed the jury that the requisite unlawful
intent concerns U.S. export law: “[T]he government need not
prove that a defendant had read, was aware of, or had consulted
the licensing provisions of the Arms Export Control Act or the
International Traffic in Arms Regulations, or the Munitions
List . . . [but it] must prove . . . that a defendant knew that the
conduct was unlawful.” Id. The defendants did not otherwise
request any instruction on the conduct at issue.

     Consistent with the presumption that juries follow
instructions, see Richardson v. Marsh, 481 U.S. 200, 211
(1987), “a conscientious and attentive juror viewing the
instructions as a whole” would not have convicted defendants
on the basis of finding a willful mental state with respect to any
conduct other than exporting in violation of U.S. law. United
States v. Lemire, 720 F.2d 1327, 1341 (D.C. Cir. 1983). The
AECA instruction made clear that the alleged criminal act was
exporting from the United States. Because Thai customs law
governs importing into Thailand, see Appellants’ Br. 30–31, if
the jury understood Burden’s only unlawful intent was to evade
Thai customs, then it would not have found Burden understood
exporting from the United States to be unlawful. Viewed as a
whole, the AECA instruction “fairly present[s] the applicable
legal principles and standards,” Joy v. Bell Helicopter Textron,
Inc., 999 F.2d 549, 556 (D.C. Cir. 1993) (internal quotation
marks omitted), and passes the “critical inquiry [of] whether
the instructions, viewed in the aggregate, properly guided the
jurors in their deliberations,” 9C CHARLES ALAN WRIGHT &
ARTHUR R. MILLER, FEDERAL PRACTICE AND PROCEDURE
§ 2558 (3d ed.).

    The court nevertheless perceives an instructional
ambiguity about the relevant unlawful conduct. See Op. 26.
Speculating about juror conduct, the court concludes that
                                 4
“there is some chance that the jury convicted based in part on
defendants’ evasiveness in importing to Thailand.” Op. 27.
Instead of analyzing the whole of the district court’s AECA
instruction, the court focuses on the instruction about
willfulness, and imposes a sua sponte obligation on the district
court upon retrial to instruct the jury that it must find that the
“defendants knew of the unlawfulness of the charged
unlicensed export of the items from the United States, and that
a willfulness finding cannot draw on evidence that they knew
the related, but legally and factually distinct, import of those
items into Thailand was illegal.” Op. 27.

     Of course, instructional clarity is desirable. But “the
defense had ample opportunity to make clarifying suggestions”
as this court now requires, and it did not, Lemire, 720 F.2d at
1343 — likely because defense counsel told the jury in closing
argument that evidence of Burden’s interest in evading Thai
customs law explained his behavior without providing
evidence of the requisite guilty mind with respect to the
violations of U.S. law with which he was charged, see Supp.
App. 809. Defense silence may further indicate the instructions
made clear the precise nature of the willful conduct required to
find guilt of the AECA charges. In any event, as noted, there
is no basis to conclude there is a “reasonable likelihood” the
jury misapplied the challenged instruction, Boyde v.
California, 494 U.S. 370, 380, 383 (1990), and “[t]he choice of
the [words] to be used in a particular instruction . . . is reviewed
only for abuse of discretion,” Joy, 999 F.2d at 556, for it is well
settled that “[t]he district judge need not use any particular
form of words or sequence of ideas so long as the charge as a
whole conveys to the jury a clear and correct understanding of
the applicable substantive law without confusing or misleading
them.” WRIGHT & MILLER § 2556. “Jurors do not sit in solitary
isolation booths parsing instructions for subtle shades of
meaning in the same way that lawyers might”; instead,
                               5
“commonsense understanding of the instructions in the light of
all that has taken place at the trial [is] likely to prevail over
technical hairsplitting.” Boyde, 494 U.S. at 380–81.

    For these reasons I concur in part and concur in the
judgments.
