NOT RECOMMENDED FOR PUBLICATION File Name: 23a0341n.06
No. 22-5984
UNITED STATES COURT OF APPEALS FILED FOR THE SIXTH CIRCUIT Jul 25, 2023 DEBORAH S. HUNT, Clerk ) UNITED STATES OF AMERICA, ) Plaintiff-Appellee, ) ) ON APPEAL FROM THE v. ) UNITED STATES DISTRICT ) COURT FOR THE WESTERN CHRISTOPHER ROBERT HARPER, ) DISTRICT OF TENNESSEE Defendant-Appellant. ) ) OPINION
Before: McKEAGUE, GRIFFIN, and MURPHY, Circuit Judges.
GRIFFIN, Circuit Judge.
Defendant Christopher Harper claims he had a right to examine confidential software law
enforcement used to download child pornography from his computer to ensure that it performed
as the government proclaimed. The district court denied his motion to compel, and a jury convicted
him of possessing child pornography. On appeal, he challenges that denial and the sufficiency of
the evidence supporting his conviction. We affirm.
I.
As part of an investigation into the distribution of child pornography, FBI special agent
Stephen Lies used a software designed for law-enforcement purposes called “Torrential
Downpour” to search the BitTorrent peer-to-peer file-sharing network for illicit materials. With
that network “a typical user . . . [generally] receive[s] multiple pieces of a file from several
different sources,” but the software Lies used allowed him to conduct “single-source No. 22-5984, United States v. Harper
downloads”—i.e., from a sole IP address. See United States v. Clark, 24 F.4th 565, 570 (6th Cir.
2022) (brackets omitted). Lies identified a computer offering for download several files with titles
suggesting child pornography and was able to download a partial “video file [that] depicted a
prepubescent female appearing to be under 12 years of age engaged in masturbating a male, vaginal
sex, and the lascivious exhibition of the pubic area.”
Lies traced the IP address to a house in Memphis, Tennessee, and interviewed its residents.
He learned that Harper lived at the house when the video was downloaded. So Lies interviewed
Harper, who both confirmed he used to live at that house and that he owned a laptop, which he
agreed to make available to law enforcement. Lies searched the laptop and discovered—despite
its having the operating system reinstalled (to perhaps clear it of incriminating evidence)—several
deleted files indicative of child pornography. Those included numerous file names referencing
child pornography, as well as searches conducted on the BitTorrent network that are “commonly
used to search for image and video files depicting prepubescent minors engaged in sexually
explicit conduct.” Although the video Lies downloaded was not there, a deleted file with the same
name was.
A grand jury indicted defendant on two counts: (1) distributing child pornography in
violation of 18 U.S.C. § 2252(a)(2); and (2) possessing child pornography in violation of 18 U.S.C.
§ 2252(a)(4)(B). Before trial, Harper broadly moved to compel the government to produce an
installable version of the Torrential Downpour software, as well as the user manual, training
materials, and source code. A magistrate judge denied Harper’s motion following an evidentiary
hearing, which the district court adopted. A jury subsequently convicted defendant on the
possession count, and the district court imposed a sixty-three month sentence.
-2- No. 22-5984, United States v. Harper
II.
Harper first asserts the district court erroneously denied his motion to compel the
production of information about Torrential Downpour. On abuse-of-discretion review, United
States v. Pirosko, 787 F.3d 358, 365 (6th Cir. 2015), we discern no error meriting reversal.
The Federal Rules of Criminal Procedure require the government to produce, “[u]pon a
defendant’s request,” all “data” and “documents” (among other things) that are “material to
preparing the defense.” Fed. R. Crim. P. 16(a)(1)(E)(i). But when the request seeks information
cloaked in law enforcement privilege, we must weigh the competing interests of a defendant’s
articulated needs in receiving that information with the government’s desire to protect it from
disclosure. Pirosko, 787 F.3d at 365. Application of this balancing test means the government
does not have “a blank check to operate its file-sharing detection software sans scrutiny,” for the
discovery of such materials ensures “that the government’s investigative methods [are] reliable,
both for individual defendants . . . and for the public at large.” Id. at 366. Yet, given the sensitive
nature of the government’s investigative methods, we require a “defendant to produce some
evidence of government wrongdoing.” Id.
The district court concluded Harper did not satisfy this “wrongdoing” threshold. It did so
by noting that Harper’s expert, Richard Connor, admitted he had no “way to dispute or refute”
Agent Lies’s testimony, so he wanted access to the software “to see how it operated” and confirm
it worked as advertised. Other than asserting that it would be “theoretically” possible for a virus
to modify the government’s software to render it suspect, Connor offered no evidence of
governmental wrongdoing.
On review of this evidence, we cannot conclude the district court abused its discretion.
Harper “has not shown that the government engaged in wrongdoing (the only way the evidence
-3- No. 22-5984, United States v. Harper
could help his defense) in employing the technique. He commissioned an expert to evaluate the
technique, but the expert could not identify any errors in the government’s efforts.” United States
v. Harney, 934 F.3d 502, 508 (6th Cir. 2019); accord Pirosko, 787 F.3d at 366. And, as in Harney,
the government offered for Connor “to conduct a forensic examination” of the data downloaded
from Harper’s computer, which would have “reveal[ed] the computer logs, show[n] when law
enforcement officers connected to Harper’s computer, and what files were downloaded.” That
offer went unclaimed. See Harney, 934 F.3d at 508 (“Nor did Harney to our knowledge try to use
the information the United States offered to give him to show that the technique didn’t operate as
expected.”). Left with “nothing more than conjecture about what the additional evidence might
show,” Harper “comes up short.” Id.
Defendant resists this conclusion, asserting he demonstrated governmental wrongdoing
because Lies ultimately downloaded only a portion of the video. With that fact, he argues United
States v. Budziak, 697 F.3d 1105 (9th Cir. 2012), is instructive because the defendant there both
“presented evidence suggesting that the FBI may have only downloaded fragments of child
pornography files from his ‘incomplete’ folder, making it ‘more likely’ that he did not knowingly
distribute any complete child pornography files,” and “that the FBI agents could have used the . . .
Free access — add to your briefcase to read the full text and ask questions with AI
NOT RECOMMENDED FOR PUBLICATION File Name: 23a0341n.06
No. 22-5984
UNITED STATES COURT OF APPEALS FILED FOR THE SIXTH CIRCUIT Jul 25, 2023 DEBORAH S. HUNT, Clerk ) UNITED STATES OF AMERICA, ) Plaintiff-Appellee, ) ) ON APPEAL FROM THE v. ) UNITED STATES DISTRICT ) COURT FOR THE WESTERN CHRISTOPHER ROBERT HARPER, ) DISTRICT OF TENNESSEE Defendant-Appellant. ) ) OPINION
Before: McKEAGUE, GRIFFIN, and MURPHY, Circuit Judges.
GRIFFIN, Circuit Judge.
Defendant Christopher Harper claims he had a right to examine confidential software law
enforcement used to download child pornography from his computer to ensure that it performed
as the government proclaimed. The district court denied his motion to compel, and a jury convicted
him of possessing child pornography. On appeal, he challenges that denial and the sufficiency of
the evidence supporting his conviction. We affirm.
I.
As part of an investigation into the distribution of child pornography, FBI special agent
Stephen Lies used a software designed for law-enforcement purposes called “Torrential
Downpour” to search the BitTorrent peer-to-peer file-sharing network for illicit materials. With
that network “a typical user . . . [generally] receive[s] multiple pieces of a file from several
different sources,” but the software Lies used allowed him to conduct “single-source No. 22-5984, United States v. Harper
downloads”—i.e., from a sole IP address. See United States v. Clark, 24 F.4th 565, 570 (6th Cir.
2022) (brackets omitted). Lies identified a computer offering for download several files with titles
suggesting child pornography and was able to download a partial “video file [that] depicted a
prepubescent female appearing to be under 12 years of age engaged in masturbating a male, vaginal
sex, and the lascivious exhibition of the pubic area.”
Lies traced the IP address to a house in Memphis, Tennessee, and interviewed its residents.
He learned that Harper lived at the house when the video was downloaded. So Lies interviewed
Harper, who both confirmed he used to live at that house and that he owned a laptop, which he
agreed to make available to law enforcement. Lies searched the laptop and discovered—despite
its having the operating system reinstalled (to perhaps clear it of incriminating evidence)—several
deleted files indicative of child pornography. Those included numerous file names referencing
child pornography, as well as searches conducted on the BitTorrent network that are “commonly
used to search for image and video files depicting prepubescent minors engaged in sexually
explicit conduct.” Although the video Lies downloaded was not there, a deleted file with the same
name was.
A grand jury indicted defendant on two counts: (1) distributing child pornography in
violation of 18 U.S.C. § 2252(a)(2); and (2) possessing child pornography in violation of 18 U.S.C.
§ 2252(a)(4)(B). Before trial, Harper broadly moved to compel the government to produce an
installable version of the Torrential Downpour software, as well as the user manual, training
materials, and source code. A magistrate judge denied Harper’s motion following an evidentiary
hearing, which the district court adopted. A jury subsequently convicted defendant on the
possession count, and the district court imposed a sixty-three month sentence.
-2- No. 22-5984, United States v. Harper
II.
Harper first asserts the district court erroneously denied his motion to compel the
production of information about Torrential Downpour. On abuse-of-discretion review, United
States v. Pirosko, 787 F.3d 358, 365 (6th Cir. 2015), we discern no error meriting reversal.
The Federal Rules of Criminal Procedure require the government to produce, “[u]pon a
defendant’s request,” all “data” and “documents” (among other things) that are “material to
preparing the defense.” Fed. R. Crim. P. 16(a)(1)(E)(i). But when the request seeks information
cloaked in law enforcement privilege, we must weigh the competing interests of a defendant’s
articulated needs in receiving that information with the government’s desire to protect it from
disclosure. Pirosko, 787 F.3d at 365. Application of this balancing test means the government
does not have “a blank check to operate its file-sharing detection software sans scrutiny,” for the
discovery of such materials ensures “that the government’s investigative methods [are] reliable,
both for individual defendants . . . and for the public at large.” Id. at 366. Yet, given the sensitive
nature of the government’s investigative methods, we require a “defendant to produce some
evidence of government wrongdoing.” Id.
The district court concluded Harper did not satisfy this “wrongdoing” threshold. It did so
by noting that Harper’s expert, Richard Connor, admitted he had no “way to dispute or refute”
Agent Lies’s testimony, so he wanted access to the software “to see how it operated” and confirm
it worked as advertised. Other than asserting that it would be “theoretically” possible for a virus
to modify the government’s software to render it suspect, Connor offered no evidence of
governmental wrongdoing.
On review of this evidence, we cannot conclude the district court abused its discretion.
Harper “has not shown that the government engaged in wrongdoing (the only way the evidence
-3- No. 22-5984, United States v. Harper
could help his defense) in employing the technique. He commissioned an expert to evaluate the
technique, but the expert could not identify any errors in the government’s efforts.” United States
v. Harney, 934 F.3d 502, 508 (6th Cir. 2019); accord Pirosko, 787 F.3d at 366. And, as in Harney,
the government offered for Connor “to conduct a forensic examination” of the data downloaded
from Harper’s computer, which would have “reveal[ed] the computer logs, show[n] when law
enforcement officers connected to Harper’s computer, and what files were downloaded.” That
offer went unclaimed. See Harney, 934 F.3d at 508 (“Nor did Harney to our knowledge try to use
the information the United States offered to give him to show that the technique didn’t operate as
expected.”). Left with “nothing more than conjecture about what the additional evidence might
show,” Harper “comes up short.” Id.
Defendant resists this conclusion, asserting he demonstrated governmental wrongdoing
because Lies ultimately downloaded only a portion of the video. With that fact, he argues United
States v. Budziak, 697 F.3d 1105 (9th Cir. 2012), is instructive because the defendant there both
“presented evidence suggesting that the FBI may have only downloaded fragments of child
pornography files from his ‘incomplete’ folder, making it ‘more likely’ that he did not knowingly
distribute any complete child pornography files,” and “that the FBI agents could have used the . . .
software to override his sharing settings.” Id. at 1112 (citation omitted). But we see nothing in
this record that indicates Lies’s partial download of a video was in any way demonstrative of
governmental wrongdoing. See Pirosko, 787 F.3d at 365 (similarly distinguishing Budziak).
Without that showing, the district court did not abuse its discretion when it denied Harper’s motion
to compel.
-4- No. 22-5984, United States v. Harper
III.
The only other issue on appeal is whether the government sufficiently proved the elements
of possessing child pornography. A defendant claiming insufficient evidence “faces a high bar”
on appeal. United States v. Persaud, 866 F.3d 371, 379–80 (6th Cir. 2017). This is because we
must uphold a jury’s conviction if, “after viewing the evidence in the light most favorable to the
prosecution, any rational trier of fact could have found the essential elements of the crime beyond
a reasonable doubt.” Jackson v. Virginia, 443 U.S. 307, 319 (1979). We can sustain a conviction
based on circumstantial evidence alone, and the evidence need not disprove every hypothesis
except that of guilt. United States v. Lindo, 18 F.3d 353, 357 (6th Cir. 1994). A sufficiency claim
does not allow us to “weigh the evidence presented, consider the credibility of witnesses, or
substitute our judgment for that of the jury.” United States v. Jackson, 470 F.3d 299, 309 (6th Cir.
2006) (citation omitted). Rather, we “draw all available inferences and resolve all issues of
credibility in favor of the jury’s verdict.” Id. (citation omitted).
Harper asserts the government failed to prove the Torrential Downpour software worked
as Lies claimed and therefore “did not establish that a complete video was ever downloaded.” This
repackaging of his denial-of-discovery issue is not well taken. Here the jury heard how Special
Agent Lies used the Torrential Downpour software to isolate the IP address of Harper’s computer
and download a video that “depicted the sexual abuse of a prepubescent child,” which was played
at trial. And it learned that, while the specific video was no longer on Harper’s computer when
searched, residual evidence of that video was recovered (along with many other files with names
indicative of child pornography), and the video was accessed on the same day Lies downloaded it.
Based on this and other evidence, any rational trier of fact could have found that Harper
-5- No. 22-5984, United States v. Harper
“knowingly possesse[d]” a visual depiction of a “minor engaging in sexually explicit conduct.”
18 U.S.C. § 2252(a)(4)(B).
IV.
We affirm the district court’s judgment.
-6-