                       PUBLISHED


UNITED STATES COURT OF APPEALS
             FOR THE FOURTH CIRCUIT


UNITED STATES OF AMERICA,             
                Plaintiff-Appellee,
               v.
ALBERT CHARLES BURGESS, JR.,
             Defendant-Appellant.          No. 09-4584

VICKY, CHILD PORNOGRAPHY
VICTIM,
                  Amicus Curiae.
                                      
        Appeal from the United States District Court
  for the Western District of North Carolina, at Asheville.
            Lacy H. Thornburg, District Judge.
               (1:09-cr-00017-LHT-DLH-1)

                  Argued: March 23, 2012

                  Decided: July 11, 2012

Before GREGORY, KEENAN, and WYNN, Circuit Judges.



Affirmed in part, vacated in part, and remanded by published
opinion. Judge Keenan wrote the opinion, in which Judge
Wynn joined. Judge Gregory wrote a separate opinion concur-
ring in part, dissenting in part, and concurring in the judg-
ment.
2                  UNITED STATES v. BURGESS
                          COUNSEL

ARGUED: James Stephens Weidner, Jr., JAMES S. WEID-
NER, JR. ATTORNEY, Charlotte, North Carolina, for Appel-
lant. Amy Elizabeth Ray, OFFICE OF THE UNITED
STATES ATTORNEY, Asheville, North Carolina, for Appel-
lee. Paul George Cassell, UNIVERSITY OF UTAH COL-
LEGE OF LAW, Salt Lake City, Utah, for Amicus Curiae.
ON BRIEF: Lisa S. Costner, LISA S. COSTNER, P.A.,
Winston-Salem, North Carolina, for Appellant. Anne M.
Tompkins, United States Attorney, Charlotte, North Carolina,
for Appellee. James R. Marsh, MARSH LAW FIRM PLLC,
White Plains, New York; Carol L. Hepburn, CAROL L. HEP-
BURN PS, Seattle, Washington, for Amicus Curiae.


                          OPINION

BARBARA MILANO KEENAN, Circuit Judge:

   A jury convicted Albert C. Burgess, Jr., of two felonies
involving the receipt and possession of materials depicting
minors engaged in sexually explicit conduct. The district
court sentenced Burgess to a term of 292 months’ imprison-
ment, and to supervised release for life. The district court also
ordered that Burgess pay, among other things, restitution of
$305,219.86 under the Mandatory Restitution for Sexual
Exploitation of Children Act, 18 U.S.C. § 2259 (the restitu-
tion statute), for losses suffered by "Vicky," a child victim
portrayed in pornographic material in Burgess’ possession.

   Burgess challenges both his convictions and sentences on
appeal. We affirm his convictions and all aspects of his sen-
tences, except the district court’s award of restitution to the
victim. Because the district court did not make specific find-
ings regarding the elements of restitution, we vacate the resti-
tution award and remand the case to the district court for a
calculation of the loss Burgess proximately caused the victim.
                   UNITED STATES v. BURGESS                     3
                                I.

   Burgess was identified as a consumer of child pornography
during an investigation by Immigration and Customs Enforce-
ment (ICE) into websites that offered such content to paying
customers. Federal authorities linked Burgess to an offending
website using payment information that he had supplied. ICE
agents later obtained a search warrant for Burgess’ residence
in Hendersonville, North Carolina.

   The ICE agents executed the search warrant on March 6,
2008. The search was a joint effort of ICE, the United States
Postal Inspection Service (U.S.P.I.S), the North Carolina State
Bureau of Investigation, and the Henderson County Sheriff’s
Department. In their search for evidence related to the exploi-
tation of children by use of the internet, the authorities located
a personal computer and 327 compact discs. Later forensic
analysis determined that the 327 compact discs contained a
total of 784 video recordings and 4,614 images of child por-
nography. Burgess’ personal computer contained an addi-
tional seven video recordings and 121 images of child
pornography.

   Although Burgess was not present during the search, the
Sheriff’s Department located his automobile while the war-
rant was being executed and initiated a "traffic stop." Detec-
tive Patricia Redden, of the Henderson County Sheriff’s
Department, and Inspector Lisa Holman, of the U.S.P.I.S,
then interviewed Burgess, who agreed to waive his Miranda
rights. Although Burgess refused to answer questions regard-
ing his internet activity, he admitted that he was the only user
of the personal computer located in his residence.

   At the same time the interview was taking place, the federal
agents continued the search of Burgess’ residence, and
informed Redden that they had located child pornography on
Burgess’ electronic data storage devices. At that time, Redden
told Burgess that he would be charged with third-degree sex-
4                  UNITED STATES v. BURGESS
ual exploitation of a minor under North Carolina law. Redden
transported Burgess to the state magistrate’s office, obtained
an arrest warrant, and escorted Burgess to the Henderson
County jail.

   While Burgess was awaiting admission to the jail, Redden
asked him if he wished to continue speaking with her. She
informed him again of his Miranda rights and told him that
he could stop answering questions at any time. Burgess, look-
ing down at a copy of the arrest warrant, stated, "You’ve got
me." He admitted to viewing child pornography between two
and three times per week, and also informed Redden that he
knew of significant child pornography trafficking operations
in Russia and the Philippine Islands (the Philippines).

   On March 7, 2008, while released on bond, Burgess placed
a telephone call to Redden stating, "Well, I’ve got to help
myself. I’ve got to talk to somebody." He agreed to speak
with ICE Agent Patrick Wilhelm and Inspector Holman. Bur-
gess met with the federal agents at his home three days later,
signed a statement waiving his Miranda rights, and provided
details regarding his pornography sources in Russia and the
Philippines. It was Burgess’ understanding that the federal
authorities would use the information and email addresses he
had provided to assist in the investigation of these internet
pornography sources. Burgess was under the impression that
he was bargaining with the federal agents, and later testified
to this effect, stating: "You know, you’ve got to give [the gov-
ernment] something before they can give you something. You
can’t sit there, you know, and extract something from them."
Burgess also confessed to the federal agents that he viewed
child pornography for five hours per day while masturbating,
and that he did so to prevent himself from actually commit-
ting offenses on a child.

  Burgess was required to appear in state court on March 28,
2008. He failed to appear, and was arrested by the United
States Marshal’s Service in Virginia on June 10, 2008. Bur-
                      UNITED STATES v. BURGESS                            5
gess’ bond was revoked and, during the time he remained in
state custody, a federal grand jury returned a two-count indict-
ment against him on March 17, 2009. The following day, a
federal warrant was issued for his arrest.

   On March 23, 2009, the government filed an application for
a writ of habeas corpus, seeking Burgess’ transfer from state
custody to federal court for an initial appearance on his fed-
eral charges. Burgess made his initial appearance on April 14,
2009, and he was remanded for the first time to federal custody.1

   Burgess was indicted for (1) knowingly possessing visual
materials depicting a minor engaging in sexually explicit con-
duct, which were shipped in interstate commerce via com-
puter, in violation of 18 U.S.C. § 2252(a)(4)(B); and (2)
knowingly receiving visual materials depicting a minor
engaging in sexually explicit conduct, which were shipped in
interstate commerce via computer, in violation of 18 U.S.C.
§ 2252(a)(2). He was tried before a jury in November 2009,
and was convicted on both counts.

   The presentence report calculated a guideline range of
imprisonment of between 292 and 365 months. Burgess, who
was proceeding pro se at his sentencing, made a number of
objections to the presentence report. Pertinent to this appeal,
Burgess objected to a four-level sentencing enhancement, pur-
suant to U.S.S.G. § 2G2.2(b)(4), for possession of images
portraying sadistic and masochistic conduct in the sexual
exploitation of children. He also objected to a five-level sen-
tencing enhancement, pursuant to U.S.S.G. § 2G2.2(b)(5), for
engaging in a pattern of activity involving the sexual abuse or
  1
   During the time he was held in state custody on charges of third-degree
sexual exploitation of a minor, Burgess also was being held in connection
with his failure to appear in state court on March 28, 2008, and for failing
to comply with sex offender registration requirements, as mandated by
North Carolina law. The status of these charges is not disclosed in the
record.
6                     UNITED STATES v. BURGESS
exploitation of a minor. After considering Burgess’ objec-
tions, the district court adopted the findings of the presentence
report. The district court imposed a sentence of 240 months’
imprisonment with respect to Count 1, and a sentence of 292
months’ imprisonment with respect to Count 2, to be served
concurrently.

   Pursuant to the restitution statute, the government submit-
ted a request for restitution on behalf of Vicky,2 a victim of
child sexual exploitation portrayed in the materials seized
from Burgess’ residence. Noting that 18 U.S.C. § 2259 man-
dated an award of restitution, the district court ordered that
Burgess compensate Vicky in accordance with the govern-
ment’s request, in the total amount of $305,219.86.

                                    II.

  Burgess raises two challenges to his pretrial detention.
First, he asserts that the federal government violated the
Speedy Trial Act, 18 U.S.C. §§ 3161 et seq., by failing to
indict him within 30 days of his being taken into custody.
Second, Burgess argues that his Sixth Amendment right to a
speedy trial was violated, because he was indicted on federal
charges more than a year after federal authorities executed a
search warrant at his residence and state authorities first took
him into custody. Upon our review, we find no merit in either
argument.

                                    A.

    The Speedy Trial Act provides, in relevant part:

        Any information or indictment charging an individ-
        ual with the commission of an offense shall be filed
        within thirty days from the date on which such indi-
    2
    "Vicky" is a pseudonym that this victim has used throughout this litiga-
tion and other prior criminal proceedings.
                   UNITED STATES v. BURGESS                    7
    vidual was arrested or served with a summons in
    connection with such charges.

18 U.S.C. § 3161(b) (emphasis added). We review the district
court’s interpretation of the Speedy Trial Act de novo, and
any related factual findings for clear error. United States v.
Rodriguez-Amaya, 521 F.3d 437, 440 (4th Cir. 2008).

   Burgess was indicted on the present charges on March 17,
2009. Thus, the Speedy Trial Act would have been implicated
if Burgess had been arrested or served with a summons in
connection with the present charges more than 30 days prior
to March 17, 2009. See 18 U.S.C. § 3161(b). However, Bur-
gess was not transferred from state custody to federal custody
until March 24, 2009, a week after the federal authorities
obtained an indictment.

   Burgess contends, nevertheless, that his rights under the
Speedy Trial Act were activated far in advance of his transfer
to federal custody. He asserts that the involvement of the fed-
eral authorities during the investigation that led to his initial
arrest, and the engagement of the United States Marshal’s
office following his failure to appear in state court, demon-
strate the "continual involvement" of federal authorities in
Burgess’ arrest and prosecution sufficient to activate his rights
under the Speedy Trial Act. We disagree with Burgess’ argu-
ments.

   The 30-day time limit is activated under the Speedy Trial
Act when a person’s liberty is restrained for the purpose of
answering to a federal charge. United States v. Woolfolk, 399
F.3d 590, 595-96 (4th Cir. 2005) (citing United States v.
Iaquinta, 674 F.2d 260, 267 (4th Cir. 1982)); see also United
States v. Thomas, 55 F.3d 144, 148 (4th Cir. 1995) (holding
that the Speedy Trial Act only applies to a federal arrest on
a federal charge). In the present case, the investigation per-
formed by the federal authorities did not restrain Burgess’ lib-
erty. That investigation initially led to a state arrest on state
8                  UNITED STATES v. BURGESS
charges, and those state charges resulted in his restraint. Simi-
larly, the actions of the United States Marshal’s office were
taken in response to Burgess’ failure to appear in state court
on state charges, and to his flight across state lines into Vir-
ginia. Therefore, neither of those actions by federal authorities
activated the provisions of the Speedy Trial Act.

                               B.

   Burgess separately asserts that his Sixth Amendment right
to a speedy trial was violated. However, he fails to provide
any analysis supporting this assertion. We review the district
court’s legal conclusions on this issue de novo, and its factual
findings for clear error. Woolfolk, 399 F.3d at 594, 597-98.

   The Sixth Amendment provides, in relevant part, that "[i]n
all criminal prosecutions, the accused shall enjoy the right to
a speedy and public trial." U.S. Const. amend. VI. To estab-
lish a violation of this constitutional guarantee, a defendant
first must show that the Amendment’s protections have been
activated by an "arrest, indictment, or other official accusa-
tion." Woolfolk, 399 F.3d at 597 (citing Thomas, 55 F.3d at
148).

   When the Sixth Amendment’s protections have been acti-
vated by a qualifying event, we engage in the four-factor bal-
ancing test set forth in Barker v. Wingo, 407 U.S. 514 (1972),
and consider (1) whether the delay before trial was uncom-
monly long, (2) whether the government or the criminal
defendant is more to blame for that delay, (3) whether, in due
course, the defendant asserted his right to a speedy trial, and
(4) whether he suffered prejudice from the delay. See United
States v. Shealey, 641 F.3d 627, 634 (4th Cir. 2011). The
duration of the delay, in addition to being a factor in this test,
also is a threshold requirement because the defendant must
establish that the length of the delay is at least presumptively
prejudicial. Doggett v. United States, 505 U.S. 647, 651-52
(1992).
                       UNITED STATES v. BURGESS                            9
   The Supreme Court has observed that "postaccusation
delay [is] presumptively prejudicial at least as it approaches
one year." Id. at 652 n.1. We have concluded that a postaccu-
sation delay as short as eight months may qualify as presump-
tively prejudicial in cases of limited complexity. Woolfolk,
399 F.3d at 598.

   Burgess, however, does not challenge as "postaccusation
delay" the period between his federal indictment and trial.
Rather, the delay about which he complains spans the period
from the execution of the search warrant on his residence on
March 6, 2008, until he was served with the federal charges
on April 13, 2009.

   Burgess’ argument is unavailing, because a Sixth Amend-
ment claim based on federal charges is calculated beginning
when a defendant is confronted with an "arrest, indictment, or
other official accusation" related to those charges. Id. at 597
(citing Thomas, 55 F.3d at 148). For purposes of a Sixth
Amendment claim, the execution of a federal search warrant
does not qualify as a federal "accusation."3 See id. at 597-98
(noting that the only potential federal actions that could acti-
vate defendant’s speedy trial rights under the Sixth Amend-
ment after being held in state custody are the serving of the
detainer, or the issuance of the federal arrest warrant, com-
plaint, or indictment). Accordingly, because Burgess was
indicted before his arrest on the present charges, his allega-
tions regarding the time he spent in state custody do not qual-
ify as "postaccusation delay" with respect to the federal
charges at issue here.
  3
   We also note that the prejudice alleged by Burgess, that he was incar-
cerated prior to his receipt of his federal indictment, was the result of his
own failure to appear in state court on pending state charges. Burgess was
originally free on bond, and the revocation of his bond was directly related
to his flight to Virginia.
10                 UNITED STATES v. BURGESS
                              III.

   Burgess next argues that the district court erred in failing
to suppress certain statements he made to law enforcement
officers in March 2008. He asserts that he provided those
statements with the understanding that they were protected by
"informal use immunity" or "transactional immunity"
because, according to Burgess, the custom and practice in the
Western District of North Carolina is to grant such immunity
to cooperating defendants.

   When reviewing the district court’s denial of a motion to
suppress, we review factual findings for clear error, and issues
of law de novo. United States v. Holmes, 670 F.3d 586, 591
(4th Cir. 2012). We conclude that the district court did not err
in denying Burgess’ motion to suppress.

   A defendant’s alleged agreement to cooperate with law
enforcement authorities in exchange for transactional immu-
nity is governed by traditional principles of contract law, and
therefore an agreement of this nature may be express or
implied. United States v. McHan, 101 F.3d 1027, 1034 (4th
Cir. 1996). Irrespective whether the alleged agreement is
express or implied, the defendant must establish that a meet-
ing of the minds occurred such that the government agreed to
refrain from prosecuting the defendant in return for his coop-
eration. Id. (holding that the same standard applies with
respect to equitable immunity).

   In this case, Burgess can identify no action or statement on
the part of the government sufficient to establish a meeting of
the minds regarding immunity for his statements. Burgess was
informed of his Miranda rights before every exchange with
the authorities, and at no time did a law enforcement agent
make any statement or representation concerning immunity.
Additionally, the agents’ conduct cannot be viewed objec-
tively as impliedly offering immunity to Burgess or as accept-
ing such an offer from him. Indeed, Burgess’ own testimony
                   UNITED STATES v. BURGESS                    11
at trial demonstrated his mistaken belief that, despite repeated
Miranda warnings, he expected to receive a benefit from pro-
viding information to the authorities. Such a mistaken belief,
however, cannot serve as the foundation for an immunity
claim. Thus, we conclude that Burgess’ argument is wholly
unsupported by the record before us, and that the district court
did not err in denying his motion to suppress.

                               IV.

   Burgess also contends that the district court erred in
responding to a question submitted by the jury during its
deliberations. We review the form and content of the district
court’s response to the jury’s question for abuse of discretion.
United States v. Foster, 507 F.3d 233, 244 (4th Cir. 2007).

   During its deliberations, the jury asked the district court to
clarify whether Burgess had "to actually know [that the image
he was charged with unlawfully receiving] crossed state lines"
and whether he had to have "participate[d] in the action to be
breaking the law" with respect to the receipt count. Given the
compound nature of the question, the district court brought
the jury into the courtroom and asked whether "the action"
stated in the second part of the question referred to interstate
transportation. The members of the jury provided an affirma-
tive response.

   In response to the jury’s inquiry, the district court replied
that "[Burgess] [did] not have to actually know the image
crossed state lines," and that "[Burgess] [did] not have to
[have] participate[d] in the crossing of state lines." Burgess
objected to the response provided by the court. He argued that
"the action" in the second part of the question could refer to
the receipt of the image. Therefore, Burgess asserted, the dis-
trict court’s clarification could have been interpreted as reliev-
ing the government of its burden to demonstrate that he did
not receive the image unaware of any pornographic content.
In support of this argument on appeal, Burgess contends that
12                    UNITED STATES v. BURGESS
one of the jurors approached defense counsel shortly after the
verdict was announced, and stated that the "action" to which
the jurors were referring was not limited to the transportation
of images in interstate commerce, but more generally referred
to the requirement that the defendant take affirmative steps to
receive images, knowing them to be pornographic.

   In answering a jury’s question, a district court is charged
with the responsibility of responding to the apparent source of
confusion accurately, without creating prejudice. Foster, 507
F.3d at 244. An erroneous response by the district court will
require reversal "only if it is prejudicial in the context of the
record as a whole." Id.

   We find no merit in Burgess’ argument. First, any informa-
tion potentially provided by a juror in this case is barred from
consideration by Rule 606(b)(1) of the Federal Rules of Evi-
dence.4 None of the exceptions listed in Rule 606(b)(2) is
applicable here. Second, the district court employed reason-
able measures to understand the questions posed by the jury,
and responded in a direct and limited fashion. The district
court sought clarification of the questions, provided a
response, and received confirmation from the foreman that the
questions had, in fact, been answered. Thus, the district
court’s interpretation of the jury’s questions was reasonable,
and the court’s response accurately stated the relevant law.
Accordingly, we conclude that the district court responded to
the jury’s apparent source of confusion accurately and without
creating any prejudice. See Foster, 507 F.3d at 244.
  4
   Rule 606(b)(1) provides: "Prohibited Testimony or Other Evidence.
During an inquiry into the validity of a verdict or indictment, a juror may
not testify about any statement made or incident that occurred during the
jury’s deliberations; the effect of anything on that juror’s or another
juror’s vote; or any juror’s mental processes concerning the verdict or
indictment. The court may not receive a juror’s affidavit or evidence of a
juror’s statement on these matters."
                   UNITED STATES v. BURGESS                  13
                              V.

   Burgess next raises two challenges related to sentencing
enhancements imposed by the district court. First, he argues
that the evidence was insufficient to support a finding that his
offenses involved material that portrayed sadistic and mas-
ochistic conduct. Second, he contends that the evidence used
to establish a pattern of activity involving the sexual abuse or
exploitation of a minor was too remote in time to support this
sentencing enhancement.

   In assessing a district court’s application of the Sentencing
Guidelines, we review its factual findings for clear error, and
the court’s legal conclusions de novo. United States v. Hamp-
ton, 628 F.3d 654, 659 (4th Cir. 2010). We conclude that the
district court did not err in imposing the two sentencing
enhancements.

                              A.

   The first sentencing enhancement at issue provides that
"[i]f the offense involved material that portrays sadistic or
masochistic conduct or other depictions of violence, increase
by 4 levels." U.S.S.G. § 2G2.2(b)(4). Burgess objected to the
imposition of this enhancement, arguing that the images of
torture depicted on the material in his possession could have
been simulated by a computer. He contends on appeal that the
district court did not make any findings regarding which
images qualified for the enhancement, and failed to rule on
his objection.

   During trial, the government introduced a video recording
in Burgess’ possession of a five-year-old child engaged in
vaginal intercourse with an adult male. The victim’s identity
and age were verified by her birth certificate and the testi-
mony of the agent who arrested the producer of the video
recording. Given that the vaginal penetration of a five-year-
old girl by an aroused adult male would necessarily cause
14                    UNITED STATES v. BURGESS
physical pain to the victim, see United States v. Rearden, 349
F.3d 608, 615-16 (9th Cir. 2003) (collecting cases), we con-
clude, as did the district court, that Burgess’ possession of this
video recording qualified for a sentencing enhancement under
U.S.S.G. § 2G2.2(b)(4).

                                    B.

   Burgess also challenges the imposition of a five-level
enhancement based on a pattern of activity involving the sex-
ual abuse or exploitation of a minor, as provided in U.S.S.G.
§ 2G2.2(b)(5). While Burgess correctly observes that several
of the most recent incidents identified in the presentence
report reflected offenses that were reversed on appeal, the dis-
trict court did not consider those charges in imposing this
enhancement.

   Of the offenses considered by the district court, the most
recent occurred in 1985. Because of this remoteness in time,
Burgess contends that the government failed to establish a
pattern of activity involving the sexual abuse or exploitation
of a minor.

   We conclude that Burgess’ argument is without merit. In
addition to his multiple convictions for committing or
attempting to commit lewd acts upon a child under 14 years
of age, Burgess admitted to molesting between 40 and 50
minor male children. Thus, it is clear that the district court did
not err in imposing this sentencing enhancement.5
  5
    Burgess also raises a challenge to the reasonableness of his sentence,
arguing that the district court failed to account adequately for the nature
and circumstances of his offenses and his history and personal characteris-
tics, as required by 18 U.S.C. § 3553. Burgess’ argument is without merit.
The record amply demonstrates that the district court provided a sufficient,
particularized explanation of its reasoning when sentencing Burgess at the
lower end of the guidelines range.
  In addition, Burgess filed a pro se brief, as well as a number of "ad-
denda," raising several other issues. We have reviewed his contentions and
have determined that they are similarly meritless.
                    UNITED STATES v. BURGESS                    15
                               VI.

   Burgess also contends that the district court erred in order-
ing that he pay restitution to Vicky under the restitution stat-
ute, because the court did not determine that his conduct
proximately caused harm to the victim. On appeal, the gov-
ernment agrees that the district court erred by awarding resti-
tution in the amount requested by the prosecution, and asks
that the case be remanded for a determination of the loss to
the victim proximately caused by Burgess. Vicky, who partic-
ipated in this case as amicus curiae with leave of this Court,
contends that the award should stand, and that the restitution
statute at issue is not limited by a proximate causation
requirement.

   In resolving this issue, we first observe that the purpose of
the restitution statute is to "direct the defendant to pay the vic-
tim . . . the full amount of the victim’s losses." 18 U.S.C.
§ 2259(b)(1). The term "full amount of the victim’s losses" is
defined in the restitution statute as "any costs incurred by the
victim for—

    (A)    medical services relating to physical, psychiat-
           ric, or psychological care;

    (B)    physical and occupational therapy or rehabili-
           tation;

    (C)    necessary transportation, temporary housing,
           and child care expenses;

    (D)    lost income;

    (E)    attorneys’ fees, as well as other costs incurred;
           and

    (F)   any other losses suffered by the victim as a
          proximate result of the offense.
16                    UNITED STATES v. BURGESS
18 U.S.C. § 2259(b)(3) (emphasis added). The restitution stat-
ute defines "victim" as the "individual harmed as a result of
a commission of a crime" under 18 U.S.C. § 2251 et seq. 18
U.S.C. § 2259(c). The issuance of a restitution order under the
statute is mandatory. 18 U.S.C. § 2259(b)(4)(A).

   The government argued before the district court that Bur-
gess should be held "jointly and severally liable with all other
defendants [for] the full amount of Vicky’s losses." Based on
information provided by Vicky, the government sought resti-
tution in the amount of $305,219.86, representing the total
loss she allegedly had suffered to date.6 During sentencing,
the district court stated only that "[r]estitution is required. I
have [the government’s] restitution memorandum and will
order it in accordance with the restitution memorandum." The
district court accordingly ordered restitution in the amount of
$305,219.86.

   In construing the statutory language, the salient issue
before us is whether a victim’s loss attributable to a defendant
under the restitution statute is limited to losses proximately
caused by the defendant. Vicky asserts that the plain language
of the statute precludes the imposition of such a limitation.
She focuses on the restitution statute’s use of the terms "full
amount of the victim’s losses" and "any costs incurred by the
victim." 18 U.S.C. § 2259(b)(1) and (3) (emphases added).
She also notes that the only language in the restitution statute
expressly limiting recovery to losses that are the "proximate
result" of a defendant’s conduct is found in subsection (F), at
the end of an enumerated list of categories. Therefore, Vicky
argues that the limitation should apply only to this "catchall"
provision, and that the other provisions, (A) through (E),
impose liability on a defendant for all of Vicky’s losses in
  6
    Although the documentation Vicky provided indicated a total loss
amount of $401,519.86, she previously had received $96,300.00 in restitu-
tion payments. The government reduced its request in light of this prior
recovery.
                       UNITED STATES v. BURGESS                           17
those categories under a theory of general causation, regard-
less of the level of attenuation.

   We observe that we are not the first federal appeals court
to consider this issue. Several of our sister circuits already
have had occasion to address the application of the restitution
statute with respect to victims depicted in child pornography.
See United States v. Kearney, 672 F.3d 81 (1st Cir. 2012);
United States v. Aumais, 656 F.3d 147 (2d Cir. 2011); United
States v. Crandon, 173 F.3d 122 (3d Cir. 1999); In re Amy
Unknown, 636 F.3d 190 (5th Cir.), reh’g granted, 668 F.3d
776 (5th Cir. 2012); United States v. Kennedy, 643 F.3d 1251
(9th Cir. 2011); United States v. Laney, 189 F.3d 954 (9th Cir.
1999); United States v. McDaniel, 631 F.3d 1204 (11th Cir.
2011); United States v. Monzel, 641 F.3d 528 (D.C. Cir.
2011).

   Of the several circuits that have considered the general cau-
sation argument advocated by Vicky in this case, none cur-
rently has adopted such reasoning.7 Instead, the courts of
appeals have concluded that a proximate causation limitation
is applicable to the restitution statute, although these courts
have reached that conclusion using different rationales. With
the benefit of these prior analyses, we examine the issue
posed by the employment of a tort law principle in the con-
struction of a criminal statute.

  Some circuits have relied on the language of subsection (F)
of the restitution statute to conclude that a proximate causa-
  7
   The Fifth Circuit originally adopted a general causation analysis in In
re Amy Unknown, 636 F.3d 190, and concluded that the "proximate cause"
limitation applied only to the catchall provision in subsection (F). Accord-
ingly, that court held that all defendants convicted of offenses against that
particular victim were jointly and severally liable for the full amount of
her loss. A later panel of that court, constrained by the precedent of In re
Amy, criticized its reasoning. See United States v. Wright, 639 F.3d 679,
686-92 (5th Cir. 2011). Following Wright, the Fifth Circuit granted en
banc review of In re Amy, effectively vacating the opinion. 668 F.3d 776.
18                   UNITED STATES v. BURGESS
tion limitation pervades throughout the statute. See Crandon,
173 F.3d at 125 (holding that the restitution statute "requires
awarding the full amount of the victim’s losses suffered as a
proximate result of the offense," and relying on 18 U.S.C.
§ 2259(b)(3)); McDaniel, 631 F.3d at 1209 (quoting Porto
Rico Ry., Light & Power Co. v. Mor, 253 U.S. 345, 348
(1920), for the proposition that "[w]hen several words are fol-
lowed by a clause which is applicable as much to the first and
other words as to the last, the natural construction of the lan-
guage demands that the clause be read as applicable to all,"
and concluding that the statute is unambiguous). We conclude
that the language of the restitution statute is not so easily
resolved and, accordingly, we decline to adopt this line of rea-
soning.

   A plurality of circuits have employed an overlay of tradi-
tional tort principles to the statutory language to resolve the
ambiguity in the restitution statute. This approach first was
employed in Monzel, in which the defendant, like Burgess,
was convicted of possessing an image of child pornography.
That image featured a victim, "Amy," who, like Vicky, has
been actively pursuing her rights under the restitution statute.
Monzel, 641 F.3d at 530. Although Amy sought $3.3 million
in restitution, the district court had ordered that the defendant
pay only $5,000.00, characterizing the amount as "nominal,"
and acknowledging that the award was less than the dollar
amount of loss that the defendant caused Amy. Id. The district
court also declined to hold the defendant jointly and severally
liable for the entirety of Amy’s harm, citing logistical difficul-
ties. Id. at 531.

   On appeal, the District of Columbia Circuit ordered that the
district court recalculate the restitution award to reflect the
actual harm suffered by Amy.8 The court concluded that,
based on the language of the restitution statute and "tradi-
  8
   Monzel reached the circuit court on a writ of mandamus filed by Amy
challenging the restitution award in the underlying criminal case.
                   UNITED STATES v. BURGESS                   19
tional principles of tort and criminal law," all the listed cate-
gories of losses in the restitution statute require a predicate
finding of proximate causation. Id. at 535. Addressing the
statutory language, the court observed that the restitution stat-
ute directs that defendants pay restitution to the "victim" of a
crime of child sexual exploitation, and that the term "victim"
is defined as "the individual harmed as a result of" a commis-
sion of a crime. Id. (citing 18 U.S.C. § 2259(a)-(c)) (emphasis
added).

   The decision in Monzel interpreted this statutory language
in conjunction with the presumption that "a restitution statute
incorporates the traditional requirement of proximate cause
unless there is good reason to think Congress intended the
requirement not to apply." Id. at 536 (citing Sherwood Bros.
v. District of Columbia, 113 F.2d 162, 163 (D.C. Cir. 1940)).
The court recognized that Congress is "presumed to have leg-
islated against the background of our traditional legal con-
cepts," and, absent language signaling a departure, those
concepts ought to be employed. Id. (quoting United States v.
Gypsum Co., 438 U.S. 422, 437 (1978)).

   We agree with this analysis and conclude that nothing in
the text or structure of the restitution statute affirmatively
indicates that Congress intended to negate the ordinary
requirement of proximate causation for an award of compen-
satory damages. Rather, the statute’s language, which defines
a victim as one "harmed as a result of a commission" of a
defendant’s acts, invokes the well-recognized principle that a
defendant is liable only for harm that he proximately caused.

   To the extent that Congress has addressed the matter of
causation in the restitution statute, Congress has suggested
that proximate causation is a feature of the legislation. A Sen-
ate committee report on the bill setting forth the language of
the restitution statute contained the following comment:
"Mandatory restitution: This section requires sex offenders to
pay costs incurred by victims as a proximate result of a sex
20                     UNITED STATES v. BURGESS
crime." S. Rep. No. 103-138, at 56 (1993) (emphasis added);
see Kearney, 672 F.3d at 96 n.11 (noting same).

   We further are persuaded by the fact that the alternative
interpretation advanced by Vicky, which requires only general
causation rather than proximate causation, permits a measure
of loss wholly disproportionate to the harm inflicted by an
individual defendant. A general causation structure, without
the limitation imposed by a proximate causation requirement,
would expand the availability of restitution for even the most
attenuated damages.9 And, as the court in Monzel noted, an
"intervening act" or a "superseding cause," which disrupts
proximate causation, does not impact causation in fact, or
general causation. Id. at 537 n.7. Thus, the expansive interpre-
tation resulting from a general causation analysis does not
comport with the limitations suggested by the six subsections
contained within the restitution statute. Accordingly, as
observed in Monzel, while it is within Congress’ power to
abrogate the traditional requirement of proximate causation,
Congress must articulate a clearer methodology if it intends
to do so. 641 F.3d at 536-37.

   Vicky asserts, nevertheless, that applying a proximate cau-
sation limitation to the restitution statute would circumvent
the express statutory command that a defendant pay the vic-
tim "the full amount of the victim’s losses." 18 U.S.C.
§ 2259(b)(1)-(2). Vicky argues that by charging each defen-
dant who sexually exploited her with the full amount of her
losses, the statutory scheme will be given the appropriate
effect of placing the onus on the exploiters to apportion liabil-
ity among themselves, jointly and severally, for the harm that
  9
    As an example, Monzel notes that, without the requirement of proxi-
mate cause, a victim of sexual exploitation injured in a automobile acci-
dent on her way to a therapist visit to address the harm inflicted by a
defendant would be entitled to compensation from that defendant for med-
ical bills resulting from the accident. 641 F.3d at 537 n.7. But for the ther-
apy required as a result of the defendant’s actions, the victim would not
have been in the location of the accident.
                       UNITED STATES v. BURGESS                            21
they have caused, rather than placing such a burden on the
victims. We disagree with Vicky’s argument.

   That argument is not supported by the structure or text of
the statute. The phrase "full amount of the victim’s losses"
cannot be interpreted in a vacuum. This phrase is defined
within the restitution statute itself, and is composed of subsec-
tions (A) through (F). Further, an interpretation of the phrase
"full amount of the victim’s losses" that allows complete
recovery from each of hundreds of defendants who have
viewed Vicky’s image or otherwise have participated in her
exploitation necessarily would lead to a system supporting
multiple recovery. While full compensation would be unlikely
from any individual defendant, Vicky’s proposed interpreta-
tion of the restitution statute places no cap on her ultimate
recovery, and would allow her to recover the amount of her
losses many times over.10

   We also observe that the tort concept of joint and several
liability is not applicable in this context. In situations such as
Vicky’s, individuals viewing her video recordings inflict inju-
ries at different times and in different locations. Therefore,
those individuals cannot have proximately caused a victim the
same injury.11 As the court observed in Monzel, "so long as
the requirement of proximate cause applies, as it does here, a
defendant can be jointly and severally liable only for injuries
  10
      We note that, at oral argument, Vicky’s counsel assured this Court
that she did not seek more than the full amount of her loss, regardless of
the ultimate number of defendants convicted of causing her harm. We do
not doubt her sincerity on this point. Nevertheless, our interpretation of the
restitution statute cannot be predicated solely on the integrity of the victim
in the present case.
   11
      The dissent takes issue with this conclusion, suggesting that the deter-
mination whether the injuries inflicted by the defendant are divisible
should be left to the district court in the first instance. However, as
explained above, a defendant can only be responsible for the damage flow-
ing from the injury he proximately caused, and not for the injuries
inflicted by others at different times.
22                 UNITED STATES v. BURGESS
that meet that requirement." Monzel, 641 F.3d at 539 (citing
Restatement (Second) of Torts § 879 cmt. b (1979) for the
proposition that individual instances of exploitation are sepa-
rate injurious results).

   Accordingly, we reject Vicky’s proposed interpretation of
the restitution statute and join the plurality of circuits in
adopting the reasoning set forth in Monzel. We hold, there-
fore, that Burgess is only responsible for losses sustained by
Vicky that he proximately caused.

   This concept of proximate causation, while much more lim-
iting than the interpretation of the restitution statute advanced
by Vicky, need not be unworkably narrow. It is well estab-
lished that children featured in child pornography are harmed
by the continuing dissemination and possession of that por-
nography. Such images are "a permanent record of the chil-
dren’s participation and the harm to the child is exacerbated
by their circulation." New York v. Ferber, 458 U.S. 747, 759
(1982); see also Osborne v. Ohio, 495 U.S. 103, 111 (1990)
("The pornography’s continued existence causes the child vic-
tims continuing harm by haunting the children in years to
come.").

   The First Circuit employed this understanding of child sex-
ual exploitation when it developed its proximate causation
analysis in Kearney. The defendant in that case argued that
because many individuals had seen and distributed pornogra-
phy featuring the victim seeking restitution, the defendant’s
contribution "cannot be said to have caused any harm absent
specific linkage" establishing the victim’s knowledge about
his offenses. 672 F.3d at 98.

   The court disagreed, reasoning that the victim need not
prove that any single additional instance of possession of her
image by itself increased her harm. Id. Rather, the court noted
that proximate causation exists when "the tortious conduct of
multiple actors has combined to bring about harm, even if the
                   UNITED STATES v. BURGESS                   23
harm suffered by the plaintiff might be the same if one of the
numerous tortfeasors had not committed the tort." Id. Thus,
the First Circuit held that "[p]roximate cause therefore exists
on the aggregate level, and there is no reason to find it lack-
ing on the individual level." Id. (emphasis added); see also
Keeton, et al., Prosser and Keeton on Torts § 41 at 268 (5th
ed. 1984) (noting that if, as a whole, multiple individuals are
a but-for cause of harm, but application of the but-for rule to
each would absolve all, each is a cause in fact of the event);
Restatement (Third) of Torts: Liability for Physical and Emo-
tional Harm § 27 cmt. g (same); id. § 36 cmt. a (noting that
an insufficient condition may be a factual cause when com-
bined with other acts to constitute a sufficient condition).

   We find the reasoning of the First Circuit persuasive. Given
the nature of the harm inflicted by purveyors and viewers of
child pornography on their victims as recognized by the
Supreme Court in Ferber and Osborne, employment of the
concept of aggregate harm in the proximate causation analysis
best effectuates the express intent of the restitution statute.

   The establishment of proximate causation, however, is not
the true challenge of the restitution statute. The primary diffi-
culty that will face the district court on remand will be the
determination, if the court finds that proximate causation has
been established, of the quantum of loss attributable to Bur-
gess for his participation in Vicky’s exploitation. Vicky is
entitled to the "full amount" of restitution for such loss, and
we leave the calculation of such an amount to the district
court in the first instance. While the district court is not
required to justify any award with absolute precision, the
amount of the award must have a sufficient factual predicate.
Vicky’s loss is an aggregation of the acts of the person who
committed and filmed her assault, those who distributed and
redistributed her images, and those who possessed those
images. The culpability of any one defendant regarding
Vicky’s loss is dependent at least in part on the role that
defendant played with respect to her exploitation.
24                  UNITED STATES v. BURGESS
   We are confident in the skill of the district judges through-
out this circuit to ascertain the appropriate amount of restitu-
tion in a given case. Nevertheless, we are mindful of the
challenges posed in the determination of damages under the
restitution statute. Accordingly, we add our voice to that of
the Ninth Circuit in Kennedy in requesting that Congress
reevaluate the structure of the restitution statute in light of the
challenges presented by the calculations of loss to victims in
the internet age. 643 F.3d at 1266.

                               VII.

  In conclusion, we affirm Burgess’ convictions and all
aspects of his sentences except the amount of restitution
ordered by the district court, which we hereby vacate. We
remand the case to the district court for an individualized
determination of proximate causation and, if such causation is
found, for a restitution award consistent with the principles
expressed in this opinion.

                                          AFFIRMED IN PART,
                                          VACATED IN PART,
                                             AND REMANDED

GREGORY, Circuit Judge, concurring in part, dissenting in
part, and concurring in the judgment:

   I concur in the majority’s disposition of the case and in
Parts I through V. I cannot, however, join Part VI. The major-
ity’s opinion prematurely and erroneously holds that the dis-
trict court must allocate some specific amount of the
proximately caused losses to the defendant. For that reason,
I respectfully dissent from Part VI.

                                I.

   I agree with most of the majority’s reasoning. I join fully
in Parts I through V and further agree with the holding in Part
                    UNITED STATES v. BURGESS                    25
VI that 18 U.S.C. § 2259(b)(1) requires a defendant to pay
only the losses he proximately caused. But the majority does
not stop there; it goes on to consider the way in which losses
that are proximately caused by more than one offender should
be allocated. It holds that in such cases, the losses must be
apportioned among those offenders, rather than permitting the
victim to hold all of them jointly and severally liable. The
majority writes, "The primary difficulty that will face the dis-
trict court on remand will be the determination, if the court
finds that proximate causation has been established, of the
quantum of loss attributable to Burgess for his participation
in Vicky’s exploitation." Ante at 23 (emphasis added). I dis-
agree with this holding for several reasons.

   I first note that the district court has yet to make any find-
ings with respect to proximate cause. That is, at this stage of
the litigation we do not know whether Burgess proximately
caused any of Vicky’s injuries at all. The district court might
find on remand that at least some of Vicky’s injuries were
caused by Burgess; or it might not. The majority puts the cart
before the horse when it determines the manner in which
Vicky’s proximately caused losses must be allocated without
any factual finding of proximate cause in the record.

   Second, to the extent this Court deems it wise to consider
how the proximately caused losses, if any, should be allo-
cated, it incorrectly holds that those losses must be distributed
among several offenders. This position is at odds with
§ 2259’s plain language. Section 2259(b)(1) says that the dis-
trict court shall "direct the defendant to pay the victim . . . the
full amount of the victim’s losses." 18 U.S.C. § 2259(b)(1)
(emphasis added). Thus, the statute clearly requires the court
to order Burgess to pay all of the losses he proximately
caused, rather than some "quantum of loss attributable to
[him]." As we have held, if the language of a statute is clear,
we must end our inquiry and adopt that meaning. E.g., Igna-
cio v. United States, 674 F.3d 252, 254 (4th Cir. 2012);
26                 UNITED STATES v. BURGESS
United States v. Abdelshafi, 592 F.3d 602, 607 (4th Cir.
2010).

   Third, this interpretation implicitly makes factual findings
that must be left to the district court in the first instance. The
common law holds joint tortfeasors jointly and severally lia-
ble for indivisible damages. E.g., TORT LAW: RESPONSIBILITIES
AND REDRESS 517 (John C.P. Goldberg et al., eds. 2008)
("[J]oint and several liability has long been available . . . in
which two negligent actors, acting independently of one
another, caused a single indivisible harm to the plaintiff
. . . ."). As the majority recognizes, "Congress is ‘presumed
to have legislated against the background of our traditional
legal concepts,’ and, absent language signaling a departure,
those concepts ought to be employed." Ante at 19. Thus the
restitution question is resolved by asking whether Burgess
proximately caused Vicky harm. Assuming that he did, the
court must then consider whether those injuries are divisible
from the injuries caused by the other offenders who also prox-
imately harmed Vicky. If they are indivisible, then Burgess
must be held jointly and severally liable for those injuries.

   In my view, it is likely that if Burgess proximately caused
Vicky psychological injury, this injury is indivisible from the
psychological injuries proximately caused by the other
offenders. I do not believe that a fact finder could meaning-
fully say precisely x amount of Vicky’s psychological injuries
were caused by Burgess’s watching the video, that y amount
was caused by Defendant #2’s watching the same video, and
so on. But whether my intuition proves to be correct, the dis-
trict court has not made any factual findings on this question.
That is, the district court never determined whether the inju-
ries caused by the defendant are divisible. The majority,
rather than remanding the case to the district court to consider
this highly factual question, holds as a matter of law that the
injuries Burgess allegedly caused are divisible, and that the
district court must determine "the quantum of loss attributable
to Burgess."
                   UNITED STATES v. BURGESS                    27
                               II.

   The majority’s discussion of joint and several liability does
not allay my concerns. In deciding whether to adopt a proxi-
mate cause limitation on restitution, the majority considers
Vicky’s argument that "applying a proximate causation limi-
tation to the restitution statute would circumvent the express
statutory command that a defendant pay the victim ‘the full
amount of the victim’s losses.’" Ante at 20. The majority’s
response is to argue that such an interpretation

    necessarily would lead to a system supporting multi-
    ple recovery. While full compensation would be
    unlikely from any individual defendant, Vicky’s pro-
    posed interpretation of the restitution statute places
    no cap on her ultimate recovery, and would allow
    her to recover the amount of her losses many times
    over.

Id. at 21. This analysis misses the mark for two reasons. First,
it incorrectly interprets joint and several liability. While joint
and several liability gives the plaintiff the option of collecting
from any defendant she chooses, she may not recover more
than her total loss: once she collects the full amount of her
losses from one defendant, she can no longer recover from
any other. See TORT LAW, supra at 517. Second, the argument
conflates proximate causation with the allocation of losses.
The question of whether a defendant proximately caused
some injury is entirely separate from the question of how
those proximately caused losses should be allocated among
several offenders. Even if this Court adopted Vicky’s reason-
ing and held that Burgess must pay restitution for the losses
he caused (whether proximately or not), it would still have to
determine how those losses should be allocated in cases
where more than one offender caused them.

                               III.

  The majority’s treatment of the restitution order is at odds
with the plain language of the statute and implicitly makes
28                 UNITED STATES v. BURGESS
factual findings better left to the district court. For these rea-
sons, I would hold that Burgess is responsible both for the
injuries he proximately caused and for any injuries indivisible
from those that he proximately caused. I would then remand
the case to the district court to make the relevant factual find-
ings.
