## Facts

- Carsten Igor Rosenow used Yahoo and Facebook messaging to arrange sexual exploitation of children abroad and possessed sexually explicit images of children.
- Yahoo and Facebook operated private messaging services and maintained policies permitting retention of content and disclosure to address illegal activity or comply with law.
- Yahoo conducted its own abuse-detection investigation of suspected accounts, identified Rosenow’s accounts, and reported information to the National Center for Missing and Exploited Children (NCMEC); Facebook also searched Rosenow’s accounts and provided information to NCMEC.
- After Yahoo’s internal investigation, the FBI sent Yahoo a preservation request under 18 U.S.C. § 2703(f) directing it to preserve specified account records pending legal process.
- The government obtained a search warrant for Rosenow’s electronic devices based on an affidavit describing Yahoo’s findings and Facebook-provided information relayed through NCMEC.
- Rosenow was arrested upon returning to the United States; searches of his devices produced additional evidence.
- A jury in the Southern District of California convicted Rosenow of attempted sexual exploitation of a child, 18 U.S.C. § 2251(c), and possession of sexually explicit images of children, 18 U.S.C. § 2252(a)(4)(B).
- On appeal, Rosenow challenged denial of suppression motions, the § 2251(c) mens rea jury instruction, and sentencing on the possession count.

## Issues

1. Whether Yahoo and Facebook acted as government agents such that their account searches and reporting to NCMEC triggered Fourth Amendment limits.
2. Whether a warrantless preservation request under 18 U.S.C. § 2703(f), and later subpoenas for account information, constituted an unreasonable seizure or invaded a protected privacy interest.
3. Whether the warrant affidavit lacked probable cause because it did not include actual images or detailed descriptions of child pornography.
4. Whether the jury instructions misstated the mental-state requirement for attempted sexual exploitation under 18 U.S.C. § 2251(c).
5. Whether the district court committed reversible error in sentencing on the possession count.

## Decision

- The Ninth Circuit affirmed the convictions and sentence.
- Yahoo and Facebook were not government actors when they searched Rosenow’s accounts and reported to NCMEC; the Fourth Amendment did not apply to those private searches.
- The § 2703(f) preservation request was not an unreasonable seizure.
- Rosenow lacked a legitimate expectation of privacy in the limited non-content records sought by subpoena, and the subpoenas did not obtain communication content.
- The search warrant was supported by probable cause under the totality of the circumstances.
- The challenged jury instruction and the sentencing rulings did not warrant reversal.

## Legal Principles

- A private party’s search does not implicate the Fourth Amendment unless the private party acted as an instrument or agent of the government (government instigation or direction is required).
- Statutory reporting duties related to child exploitation do not, without government direction of a particular search, convert provider abuse-detection activity into governmental action.
- A preservation request under 18 U.S.C. § 2703(f) requires a provider to preserve records already in its possession pending legal process and does not, by itself, constitute an unreasonable seizure.
- Under the third-party doctrine, a defendant generally lacks a reasonable expectation of privacy in non-content subscriber and routing records voluntarily conveyed to service providers for account administration.
- Probable cause does not require attaching contraband images to a warrant application if the affidavit’s factual narrative establishes a fair probability that evidence will be found in the place to be searched.

## Conclusion

The Ninth Circuit upheld the denial of suppression and affirmed Rosenow’s convictions and sentence, holding that provider-led account investigations and NCMEC reporting were private action, § 2703(f) preservation was not an unreasonable seizure, subpoenas for non-content records did not invade a protected privacy interest, and the warrant, jury instruction, and sentencing rulings were legally sufficient.


United States v. Rosenow, 33 F.4th 529 (9th Cir. 2022)