Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 1 FILED United States Court of Appeals PUBLISH Tenth Circuit
UNITED STATES COURT OF APPEALS May 12, 2025
Christopher M. Wolpert FOR THE TENTH CIRCUIT Clerk of Court _________________________________
UNITED STATES OF AMERICA,
Plaintiff - Appellee,
v. No. 23-2017
GUY ROSENSCHEIN,
Defendant - Appellant. _________________________________
Appeal from the United States District Court for the District of New Mexico (D.C. No. 1:16-CR-04571-JCH-1) _________________________________
Submitted on the briefs:*
Guy R. Rosenschein, New Mexico, pro se Defendant-Appellant.
Alexander M.M. Uballez, United States Attorney, and Tiffany L. Walters, Assistant United States Attorney, Albuquerque, New Mexico, for Plaintiff-Appellee. _________________________________
Before HARTZ, EID, and CARSON, Circuit Judges. _________________________________
EID, Circuit Judge. _________________________________
* After examining the briefs and appellate record, this panel has determined unanimously that oral argument would not materially assist in the determination of this appeal. See Fed. R. App. P. 34(a)(2); 10th Cir. R. 34.1(G). The case is therefore ordered submitted without oral argument. Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 2
In 2016, an anonymous user uploaded images of child pornography to
Chatstep, an internet chatroom service. Using a Microsoft product called PhotoDNA,
Chatstep identified and reported the uploads to the National Center for Missing &
Exploited Children (“NCMEC”). Based on location data derived from the IP address
accompanying the files, NCMEC forwarded the reports to the Bernalillo County
Sheriff’s Office (“BCSO”) in New Mexico. BCSO investigated the reports,
identified the user as Guy Rosenschein, and obtained a warrant to search
Rosenschein’s home in Albuquerque. The search uncovered approximately 21,000
images and videos of child pornography on electronic devices in Rosenschein’s
possession.
A grand jury indicted Rosenschein on charges of possession and distribution of
child pornography, in violation of 18 U.S.C. §§ 2252A(a)(2), 2252A(a)(5)(B),
2252A(b)(1), and 2256. Rosenschein filed three pre-trial motions in response. First,
Rosenschein moved to suppress the evidence of his uploads, arguing that Chatstep’s
warrantless search of his files through PhotoDNA violated the Fourth Amendment.
He also claimed that, as a result of that unlawful search, any evidence of child
pornography found in his home should be suppressed under the exclusionary rule.
Second, Rosenschein moved to dismiss the case, or, in the alternative, to compel the
discovery of the computer programs used by Microsoft and NCMEC to generate
reports of child pornography. And third, Rosenschein moved to compel the
government to require expert reports for two of its witnesses before the suppression
hearing.
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The district court denied each of Rosenschein’s motions. Rosenschein
subsequently pleaded guilty to one count of possession of child pornography and
seven counts of distribution of child pornography, reserving his right to appeal the
district court’s decision to deny his motions.
Exercising jurisdiction under 28 U.S.C. § 1291, we affirm the district court’s
denial of all three motions. First, because Chatstep and Microsoft were not acting as
governmental agents, the Fourth Amendment does not protect Rosenschein from their
conduct. Further, even if Chatstep and Microsoft were governmental agents,
Rosenschein’s Fourth Amendment claim fails because he had no reasonable
expectation of privacy in images he uploaded to a reportable internet chatroom with
strangers. Second, the district court did not abuse its discretion in denying
Rosenschein’s motion to require production of NCMEC’s reporting system because
Rosenschein had the opportunity to access that information through the examination
of witnesses. Finally, the district court did not abuse its discretion in refusing to
require expert reports for the government’s witnesses because Rosenschein conceded
that Federal Rule of Criminal Procedure 16(a)(1)(G)—which generally requires the
government to produce expert reports for witnesses it intends to call during its case-
in-chief—does not apply to suppression hearings.
I.
As part of its efforts to combat child victimization, NCMEC operates the
CyberTipline, which functions as a “national online clearinghouse for tips and leads
about child exploitation.” Supp. R. Vol. IV at 71. Federal law requires electronic
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service providers (“ESPs”) to report to NCMEC any apparent child pornography of
which they are aware. 18 U.S.C. §§ 2258A(a)(1), (f). It does not, however, compel
ESPs to affirmatively search for child pornography. Id.
In July and August of 2016, Chatstep submitted two CyberTipline reports to
NCMEC after detecting several uploads of pornographic images by a user named
“Carlo.” Chatstep uses a Microsoft program called PhotoDNA to scan the “hash
values” of suspect files on its site and compare them to the list of hash values of
known child pornography images already in circulation.1 A “hash match” occurs
when an uploaded image’s hash value matches the hash value of a known image of
child pornography.
Each of Chatstep’s reports included the uploaded image and the IP address of
the user. NCMEC investigated the reports and traced the IP address to a computer in
Albuquerque, New Mexico, with CenturyLink as its internet service provider.
NCMEC referred the information to the Internet Crimes Against Children (“ICAC”)
Task Force at the Office of the New Mexico Attorney General, which obtained grand
jury subpoenas for CenturyLink. CenturyLink identified “rosenscheinguy” as the
1 A “hash value” is “a short string of characters generated from a much larger string of data (say, an electronic image) using an algorithm—and calculated in a way that makes it highly unlikely another set of data will produce the same value.” United States v. Ackerman, 831 F.3d 1292, 1294 (10th Cir. 2016). “Hash values have been used to fight child pornography distribution, by comparing the hash values of suspect files against a list of the hash values of known child pornography images currently in circulation.” United States v. Reddick, 900 F.3d 636, 637 (5th Cir. 2018). “This process allows potential child pornography images to be identified rapidly, without the need to involve human investigators at every stage.” Id. 4 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 5
subscriber for the IP address and gave ICAC the physical address associated with the
account. BCSO obtained and executed a search warrant for Rosenschein’s residence
and recovered a thumb drive containing child pornography. The execution of
subsequent search warrants at Rosenschein’s home revealed several additional
devices containing evidence of possession and distribution of child pornography. In
total, law enforcement discovered devices containing over 19,000 images and 2,000
videos of child pornography.
Rosenschein was indicted by a grand jury for possession and distribution of
child pornography in violation of 18 U.S.C. §§ 2252A(a)(2), 2252A(a)(5)(B),
2252A(b)(1), and 2256. Rosenschein moved to suppress all the evidence of child
pornography. He alleged that Microsoft and Chatstep were acting as agents for
NCMEC—and thus agents for the government, see United States v. Ackerman, 831
F.3d 1292, 1295–304 (10th Cir. 2016)—when they created and used PhotoDNA to
scan the images uploaded to Chatstep without a warrant.
Rosenschein also moved to suppress the evidence under Franks v. Delaware,
438 U.S. 154 (1978). He argued that the search warrant affidavit contained
materially false or misleading statements and omitted information intentionally or
with reckless disregard for the truth. He further claimed that, without these false
statements and omissions, the warrant to search his home could not have lawfully
issued.
Beyond his suppression motion, Rosenschein moved to compel discovery of
the computer algorithm used by NCMEC for CyberTipline reports from ESPs. He
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also framed this motion as a motion to dismiss the case based on failure to produce
evidence. Finally, he moved to require the government to disclose expert reports for
the Microsoft and NCMEC witnesses it planned to call at the suppression hearing.
The district court denied each of Rosenschein’s motions. Under a Rule
11(c)(1)(C) plea agreement, Rosenschein pleaded guilty to seven counts of
distribution and one count of possession of child pornography. Rosenschein reserved
his right to appeal the denial of his suppression motions, his motion to dismiss the
case or compel discovery, and his motion for expert reports. The district court
sentenced Rosenschein to 210 months’ imprisonment, and Rosenschein timely
appealed.
II.
We begin by addressing the district court’s denial of Rosenschein’s
suppression motions. Following the denial of a motion to suppress evidence, we
review the district court’s legal determinations de novo and its factual findings for
clear error. United States v. Muhtorov, 20 F.4th 558, 592 (10th Cir. 2021). A district
court’s factual finding is made in clear error only if “the error [is] pellucid to any
objective observer,” the finding is “without factual support in the record,” or the
panel is “left with a definite and firm conviction that a mistake has been made.”
United States v. Madrid, 713 F.3d 1251, 1256–57 (10th Cir. 2013) (quotations
omitted). In conducting this review, “we view the evidence in the light most
favorable to the government.” Muhtorov, 20 F.4th at 592 (quotation omitted).
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A.
Rosenschein first argues that Microsoft and Chatstep violated his Fourth
Amendment right to be free from unreasonable searches and seizures when they
created and used PhotoDNA to search his Chatstep uploads without a warrant. We
disagree. Because Microsoft and Chatstep were not acting as governmental agents,
their actions cannot implicate the Fourth Amendment. And even if they were
governmental agents, Rosenschein’s claim fails because he had no reasonable
expectation of privacy in images he uploaded to a reportable internet chatroom with
strangers.
The Fourth Amendment protects “[t]he right of the people to be secure in their
persons, houses, papers, and effects, against unreasonable searches and seizures[.]”
U.S. Const. amend. IV. Its protections do not apply against “private individual[s] not
acting as [] agent[s] of the [g]overnment or with the participation or knowledge of
any governmental official.” United States v. Jacobsen, 466 U.S. 109, 113 (1984)
(quotation omitted); see United States v. Koerber, 10 F.4th 1083, 1114 (10th Cir.
2021) (“Fourth Amendment concerns [] are not implicated when a private person
voluntarily turns over property belonging to another and the government’s direct or
indirect participation is nonexistent or minor.” (quotation omitted)). Accordingly,
the first step in a Fourth Amendment search claim is to determine the extent of the
government’s involvement in the search.
To determine whether a private party is acting as a governmental agent, we
employ a two-pronged inquiry. United States v. Souza, 223 F.3d 1197, 1201 (10th
7 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 8
Cir. 2001). First, we ask “whether the government knew of and acquiesced in the
[party’s] intrusive conduct[.]” Id. (quotation omitted). Second, we consider
“whether the party performing the search intended to assist law enforcement efforts
or to further his own ends.” Id. (quotation omitted). “Both prongs must be satisfied
considering the totality of the circumstances before the seemingly private search may
be deemed a government search.” United States v. Poe, 556 F.3d 1113, 1123 (10th
Cir. 2009).
Here, neither Chatstep nor Microsoft was a governmental agent because each
“acted to further [its] own ends.” Souza, 223 F.3d at 1201 (quotation omitted). As
the district court noted, Chatstep began monitoring its site for child pornography out
of concern that the presence of child pornography would hurt the company’s
reputation, drive away users, and violate advertisers’ policies. Chatstep
independently turned to PhotoDNA to automate the monitoring of child pornography;
it was not directed by a government entity to use that product. Instead, Chatstep
found PhotoDNA after conducting a web search and applied twice before receiving
approval to use the product.2
2 Rosenschein claims NCMEC improperly coerced Chatstep into registering for the CyberTipline, thus making Chatstep a governmental agent. But even after receiving multiple emails from NCMEC about the program, Chatstep waited approximately one year to register. And though Rosenschein correctly notes that Chatstep went beyond its legal obligations to assist law enforcement, Chatstep provided several independent business reasons for doing so. See, e.g., R. Vol. III at 615 (noting Chatstep’s decision to cooperate with the government to receive “free moderation” of child pornography on the site); id. at 288, 368–70, 614 (noting that providing the government with direct access to logs saved Chatstep time). Put differently, Chatstep’s decision to involve the government advanced an independent 8 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 9
Microsoft’s sole tie to the Rosenschein investigation was its creation of
PhotoDNA. But Microsoft’s independent creation of a product that assists both
private and public parties in combatting the distribution of child pornography does
not transform it into a governmental agent. See United States v. Alexander, 447 F.3d
1290, 1297 (10th Cir. 2006) (noting that “an agency relationship does not develop
where the government is an incidental beneficiary of another party’s actions”). And
here, the record contains ample evidence showing that Microsoft created PhotoDNA
to advance its independent business interests. See, e.g., R. Vol. III at 741–42
(“Protecting our brand and our reputation means reducing illegal and harmful
activities on our services.”); id. at 100–02 (noting that Microsoft creates similar
services and offers them to third-party platforms as part of its “vision in protecting
customers more broadly,” “purg[ing] the ecosystem of explicit material[,] . . . [and
making] it a better environment for [Microsoft] to operate in”).3
interest because, as previously noted, child pornography negatively affected business. See United States v. Rosenow, 50 F.4th 715, 735 (9th Cir. 2022) (“[A] private party’s otherwise legitimate, independent motivation is not rendered invalid just because law enforcement may further its interests.”). 3 Rosenschein also challenges the district court’s exclusion of Exhibit AD, which consists of documents from Soto v. Microsoft, No. 16-2-31049-4 (Super. Ct. Wash. 2016), a civil case. He contends the court should have taken judicial notice of Microsoft’s “Policy Overview”—which discusses changes in how Microsoft handled reports of child sexual abuse material on its private services—because that document “concern[ed] Microsoft’s understanding of both being an agent of the state and how to take actions to better assist law enforcement during criminal prosecutions.” R. Vol. II at 286. We conclude the district court did not abuse its discretion in denying Rosenschein’s motion for three reasons: (1) the documents dealt with Microsoft’s policies for private services, while this case concerns Microsoft’s licensing of PhotoDNA for the public; (2) the documents did not bear a direct relation to Rosenschein’s case and their accuracy can be reasonably questioned; and (3) in any 9 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 10
Rosenschein claims our decision in Ackerman requires us to conclude that
Chatstep and Microsoft were governmental agents. There, we held that NCMEC
acted as a governmental agent when it opened an email and four attachments
forwarded by AOL through the CyberTipline. Ackerman, 831 F.3d at 1295–300. We
further noted that it is a “misreading” of precedent to suggest that “a private party
who bears any private purpose cannot serve as a governmental agent.” Id. at 1303.
But Ackerman provides little guidance to us here because the key facts that led us to
determine that NCMEC was a governmental agent are absent in this case. Unlike
NCMEC, which receives its funding from Congress for the purpose of stopping the
spread of child pornography and seeks tips “precisely because (at least in part) it
intends to aid law enforcement,” id. at 1302, Congress has expressly stated that
ESPs—such as Chatstep and Microsoft—need not affirmatively search for child
pornography, 18 U.S.C. § 2258A(f). Instead, unlike NCMEC, both Chatstep and
Microsoft acted to protect their legitimate private business interests. Cf. United
States v. Sykes, 65 F.4th 867, 877 (6th Cir. 2023) (concluding that Facebook was not
a governmental agent where its search was motivated by “an independent business
purpose for keeping its platform safe and free of child-exploitation content”). Thus,
case, judicial notice would not have changed the district court’s ruling because the documents support the court’s conclusion that Microsoft acted according to its independent business interests. 10 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 11
Rosenschein’s Fourth Amendment claim fails under the second prong of the
governmental-agent inquiry.4 Souza, 223 F.3d at 1201.
Even if Chatstep and Microsoft were governmental agents, Rosenschein’s
Fourth Amendment claim falls short because he has not presented evidence sufficient
to establish a Fourth Amendment search. The Supreme Court has identified two
types of searches that give rise to a Fourth Amendment claim. First, “[w]hen an
individual seeks to preserve something as private, and his expectation of privacy is
one that society is prepared to recognize as reasonable, . . . [an] official intrusion into
that private sphere generally qualifies as a search and requires a warrant supported by
probable cause.” Carpenter v. United States, 585 U.S. 296, 304 (2018) (quotation
and internal quotation marks omitted). Second, a Fourth Amendment search occurs
where the government “physically occupie[s] private property for the purpose of
obtaining information.” United States v. Jones, 565 U.S. 400, 404–05 (2012).
On appeal, Rosenschein has not argued that the conduct in this case amounted
to a physical trespass for the purpose of obtaining information. Accordingly, we
4 Rosenschein also argues that the district court should have invalidated the entire PhotoDNA program based on NCMEC’s alleged violation of an earlier version of 18 U.S.C. § 2258C(a)(1). Specifically, he argues that the court should have suppressed all the evidence because NCMEC was statutorily prohibited from including in its hash list any PhotoDNA hash values of images of unidentified children. We need not address this argument in depth. We have long held that suppression is available for a statutory violation only where the statute provides for such a remedy. See United States v. Minjares-Alvarez, 264 F.3d 980, 986 (10th Cir. 2001). The statute here does not. 11 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 12
deem that argument waived. See United States v. Leffler, 942 F.3d 1192, 1196 (10th
Cir. 2019).
Rosenschein’s claim that he had a reasonable expectation of privacy in his
uploads also fails. The Fourth Amendment offers no protection for items “knowingly
expose[d] to the public.” United States v. Miller, 425 U.S. 435, 442 (1976). This
principle is based on the common-sense understanding that “[t]hose who bring
personal material into public spaces, making no effort to shield that material from
public view, cannot reasonably expect their personal materials to remain private.”
United States v. Barrows, 481 F.3d 1246, 1249 (10th Cir. 2007). Here, several facts
support the district court’s conclusion that Rosenschein has not demonstrated an
objectively reasonable expectation of privacy in the images he uploaded to Chatstep.
For example, Chatstep is a free, publicly accessible website. Rosenschein understood
that he was sharing child pornography with strangers online. And though
Rosenschein claims his expectation of privacy was reasonable because the images
were (or could have been) uploaded in a private, password-protected chatroom with a
single recipient, he has offered no evidence to establish this fact.
Chatstep’s inclusion of a “report image” function—which, when utilized,
allowed users to view the IP address of the image’s sender—further supports this
conclusion. Chatstep created this feature “as a deterrent to Chatstep users sharing
illegal photos because they would know that other users could report them” either to
Chatstep or to law enforcement. R. Vol. II at 330. Thus, even in a small chatroom
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with generally anonymous users, no reasonable user would have believed that images
uploaded to Chatstep would remain private.
Both our precedents and several out-of-circuit cases also reaffirm what
common sense makes clear: Individuals have no reasonable expectation of privacy in
images they post to a reportable online chatroom with strangers. See, e.g., United
States v. Morel, 922 F.3d 1, 10 (1st Cir. 2019) (concluding that a defendant had no
reasonable expectation of privacy in images uploaded to a publicly accessible image
hosting website); United States v. Lifshitz, 369 F.3d 173, 190 (2d Cir. 2004)
(“Individuals generally possess a reasonable expectation of privacy in their home
computers. . . . They may not, however, enjoy such an expectation of privacy in
transmissions over the Internet or e-mail that have already arrived at the recipient.”);
Guest v. Leis, 255 F.3d 325, 336 (6th Cir. 2001) (holding, in a non-criminal context,
that “computer users do not have a legitimate expectation of privacy in their
subscriber information because they have conveyed it to another person—the system
operator”); United States v. Perrine, 518 F.3d 1196, 1205 (10th Cir. 2008)
(concluding that a defendant had no reasonable expectation of privacy in subscriber
information given to an internet provider); United States v. Charbonneau, 979 F.
Supp. 1177, 1185 (S.D. Ohio 1997) (concluding that a defendant had no reasonable
expectation of privacy in statements made in AOL chatrooms in part because the
defendant “ran the risk of speaking to an undercover agent”). Accordingly, we reject
Rosenschein’s first set of arguments for suppressing the evidence under the Fourth
Amendment.
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B.
Rosenschein next argues the district court should have suppressed the evidence
found in his home under Franks v. Delaware, 438 U.S. 154 (1978). To establish a
Fourth Amendment violation under Franks, a defendant must show that “(1) an
officer’s affidavit supporting a search warrant application contains a reckless
misstatement or omission that (2) is material because, but for it, the warrant could not
have lawfully issued.” United States v. Moses, 965 F.3d 1106, 1110 (10th Cir. 2020)
(quotation omitted). Because we identify no materially false statements or wrongful
omissions in the search warrant affidavit, we affirm the district court’s denial of
Rosenschein’s suppression motion.
Rosenschein challenges three statements as materially false or misleading.
First, he argues the affidavit’s claim that “using hash values is another common
technique used to identify users and specific electronic files” is false because
PhotoDNA identifies only images, and not users or other electronic files. Supp. R.
Vol. IV at 43; Aplt. Br. at 30. But this statement refers to hash values generally—
which can be used on usernames, passwords, and email addresses, or to determine
what user saved or uploaded a file, see R. Vol. III at 471–72—and not merely to
PhotoDNA’s capabilities. Thus, the statement is accurate. Although it is not wholly
applicable to PhotoDNA—the only product used in this case—it was not intentionally
or recklessly misleading. See id. at 564–65 (explaining that the detective who
authored the affidavit did not understand the precise differences between
PhotoDNA’s hash values and hash values generally).
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Second, Rosenschein contends the affidavit’s claim that “hash values are
mathematical algorithms that produce a 25-character pattern that is specific to a
single file” is false because hash values are the product of algorithms, and not
themselves algorithms. Supp. R. Vol. IV at 43; Aplt. Br. at 30. But whether hash
values are algorithms or products of algorithms is immaterial. As the affidavit makes
clear, “the salient point for purpose[s] of a probable cause determination is that a
hash value is unique to any given image and thus is a reliable way to identify an
image.” R. Vol. II at 368. And here, the government has provided ample evidence
that hash values are a reliable way to identify an image. See R. Vol. III at 89–90
(describing PhotoDNA’s error rate as one in fifty billion); id. at 166, 177 (explaining
that PhotoDNA has an accuracy rate of over ninety-nine percent); id. at 91, 213
(stating that false positives—that is, matches that are not child pornography—are
extremely rare).
Third, Rosenschein claims that the authoring detective’s statement that
“Chatstep provided the photograph . . . I reviewed it” was misleading. Supp. R. Vol.
IV at 44–45; Aplt. Br. at 31. Specifically, he argues that the term “review” may have
misled the judge issuing the warrant to believe that Chatstep had also viewed the
images. We agree with the district court that this language did not reasonably
suggest that Chatstep had viewed the images. And even if the language was
ambiguous, we conclude the mistake was immaterial because the affidavit correctly
stated that a detective had viewed the images and confirmed that they contained child
pornography before applying for the warrant.
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Rosenschein also claims the affidavit omitted several key facts. First, he notes
that the affidavit did not include a detailed description of PhotoDNA. But he does
not explain how this omission negated probable cause. And in any event, the
government has offered significant evidence showing that PhotoDNA is a reliable
method of identifying child pornography. See supra p. 15. Thus, Rosenschein has
not shown this omission was material.
Second, Rosenschein argues that the affidavit wrongly omitted information
about NCMEC’s role in the investigation. He also contends the affidavit was
misleading because it did not disclose that the reported images were not viewed or
verified by NCMEC. But the record directly contradicts these claims. The affidavit
described in detail NCMEC’s role in forwarding CyberTips to ICAC and explained
that local law enforcement received information from ICAC. Further, as previously
noted, the affidavit explained that a detective had viewed the images and described
their content before applying for the warrant.
Third, Rosenschein contends that the district court should have suppressed all
evidence from the search of his home because the affidavit used to obtain the search
warrant did not inform the issuing judge that a detective had viewed the Chatstep
uploads without obtaining a warrant. This omission is immaterial; as the district
court correctly concluded, the detective did not need a warrant to view Rosenschein’s
uploads because they were posted to a reportable chatroom with strangers. See supra
pp. 11–13. Further, Rosenschein has presented no evidence that suggests the
omission was made to mislead the court.
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Fourth, Rosenschein argues the affidavit wrongly omitted important
information about the investigative process. For example, he notes that the affidavit
did not state that law enforcement had corroborated the IP address listed in the
CyberTips. This omission is immaterial. Rosenschein does not explain how the
absence of a corroboration statement would have affected the judge’s probable cause
determination, particularly where law enforcement had no reason to believe the
information in the CyberTips was unreliable.
Finally, Rosenschein argues that the affidavit’s description of the images as
“depict[ing] a child under 18 years old involved in a sex act” was conclusory and
thus did not permit the judge to determine that there was probable cause to search
Rosenschein’s home. Supp. R. Vol. IV at 44–45; Aplt. Br. at 31–32. He contends
that the affidavit should have described the particular sex act. This claim directly
contradicts our precedents. We have previously held that generalized descriptions of
child pornography sufficiently convey to the judge issuing the search warrant the
type of evidence required to support probable cause. United States v. Simpson, 152
F.3d 1241, 1247 (10th Cir. 1998). Further, the affidavit’s description aligns with the
legal definition of child pornography. See 18 U.S.C. § 2256(8) (defining child
pornography as “any visual depiction . . . of a minor engaging in sexually explicit
conduct”). Thus, the affidavit’s description of the images was adequate.
Rosenschein has not shown that the affidavit contained false statements or
relevant omissions such that the warrant should not have issued. See Franks, 438
U.S. at 171–72. Accordingly, based on the information provided in the affidavit, the
17 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 18
district court correctly concluded that the government’s evidence was sufficient to
establish probable cause to justify the search of Rosenschein’s home.
III.
Rosenschein next challenges the district court’s denial of his motion to either
dismiss the case or, in the alternative, to compel the discovery of the computer
programs used by Microsoft and NCMEC to produce internal reports. To support his
claim, he argues that Chatstep, Microsoft, and NCMEC conspired to destroy or
withhold evidence as part of their effort to frame him for possessing and uploading
images he never possessed.
We begin with Rosenschein’s claim that the district court should have
dismissed the case based on Chatstep’s failure to preserve evidence of the uploaded
images after they were reported to NCMEC. “[U]nless a criminal defendant can
show bad faith on the part of the police, failure to preserve potentially useful
evidence does not constitute a denial of due process of law.” Arizona v. Youngblood,
488 U.S. 51, 58 (1988). Here, Rosenschein has not shown that Chatstep’s alleged
failure to preserve electronic records after it reported the images to NCMEC
constitutes bad faith on the part of the government. As previously discussed,
Chatstep is not a governmental agent. See supra pp. 8–11. Further, nothing in the
record suggests that Chatstep destroyed evidence at the government’s direction or
request. To the contrary, Chatstep’s loss of data also precluded the government from
using that information to support its case. Thus, Chatstep’s failure to preserve
evidence is not a basis for dismissal of Rosenschein’s criminal charges. See United
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States v. Fernandez, 24 F.4th 1321, 1336–39 (10th Cir. 2022) (concluding the
government was not responsible for a private party’s failure to preserve evidence).
We next turn to Rosenschein’s claim that the district court should have
compelled discovery of the computer programs and hash values used by NCMEC to
generate reports of child pornography. “We generally review for an abuse of
discretion the district court’s denial of a discovery request for documentary
evidence.” United States v. Cates, 73 F.4th 795, 811 (10th Cir. 2023) (quotation
omitted). “[W]e will not disturb the district court’s ruling unless we have a definite
and firm conviction that the court made a clear error of judgment or exceeded the
bounds of permissible choice in the circumstances.” Id. (quotation omitted).
At the hearing discussing this motion, the government stated (1) that it had
produced all the information NCMEC had regarding the images in this case; (2) that
NCMEC would present testimony regarding its child pornography database; and
(3) that it had provided the defense with an outline of NCMEC’s expected testimony
on the issue. The government further explained that it could not produce what
Rosenschein was requesting because there was no electronic report capturing the
hash values, and that the information would instead be provided through testimonial
evidence. Because Rosenschein would have had the opportunity to access that
information—albeit through the examination of witnesses, rather than a report—we
conclude that the district court did not abuse its discretion in denying Rosenschein’s
motion to require production of a report.
19 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 20
IV.
Rosenschein next claims that the district court erred in denying his motion to
require the government to provide expert reports for two witnesses—John Shehan,
who served as the vice president of the Exploited Children Division of NCMEC, and
Jeff Lilleskare, who worked as a group manager for security and online safety at
Microsoft—before the suppression hearing. See Fed. R. Crim. P. 16(a)(1)(G)
(requiring the government to produce, at the defendant’s request, expert reports for
witnesses it intends to call during its case-in-chief). He further argues that Shehan
and Lilleskare “had no knowledge of the case whatsoever, disqualifying [them] as []
factual witness[es].” Aplt. Br. at 28.
Both claims fall short. First, Rosenschein concedes that the Federal Rules of
Evidence and Federal Rule of Criminal Procedure 16(a)(1)(G) do not apply to
suppression hearings. R. Vol. I at 456 (“As a technical matter that is
true.”). Although courts may, in certain cases, exercise their discretion to order
expert reports in advance of a suppression hearing, nothing in this case suggests the
district court was required to do so. Second, the witnesses’ declarations and
testimony—as well as their positions in NCMEC and Microsoft—establish a clear
basis for their knowledge. Nothing in the record suggests that the district court
should not have permitted these witnesses to testify at the suppression hearing.
Accordingly, the district court did not abuse its discretion in denying Rosenschein’s
motion.
20 Appellate Case: 23-2017 Document: 164-1 Date Filed: 05/12/2025 Page: 21
V.
For the foregoing reasons, we AFFIRM the district court’s denial of
Rosenschein’s motions.