13 F.4th 961
9th Cir.2021Background
- Google’s automated hashing system flagged four image attachments in Luke Wilson’s Gmail account as matching images previously identified as child pornography; Google reported the matches to NCMEC without any Google employee opening Wilson’s attachments.
- NCMEC forwarded the CyberTip to the San Diego ICAC; Agent Thompson opened and viewed Wilson’s four attachments without a warrant to determine whether the matter could be investigated.
- Based on his viewing, Thompson described the images in detail in affidavits and obtained warrants for Wilson’s email account and residence; searches recovered extensive child‑pornography evidence and led to Wilson’s conviction.
- Wilson moved to suppress, arguing the warrantless government viewing violated the Fourth Amendment; the district court denied suppression, relying on the private‑search doctrine (Jacobsen/Tosti).
- The Ninth Circuit reversed: it held the government’s viewing exceeded any antecedent private search because no Google employee had viewed Wilson’s specific files and the government obtained new, critical information used to obtain warrants and to prosecute; conviction vacated and case remanded.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Whether the private‑search doctrine permits law enforcement to open and view electronic files that a provider’s automated system flagged but that no provider employee viewed | Wilson: Google did not view his files, so the private‑search exception did not eliminate his expectation of privacy; warrant required | Government: Google’s automated flagging and previous provider review of matching images effectively frustrated privacy; Thompson merely confirmed what Google already knew (Jacobsen/Tosti) | Held: Private‑search exception did not apply; government exceeded scope and needed a warrant. |
| Whether the government learned nothing new by viewing the attachments (i.e., whether law enforcement merely repeated the private search) | Wilson: Agent Thompson obtained detailed, new information (what the images actually showed and confirmation they were child pornography) that was not conveyed in the CyberTip | Government: Viewing merely confirmed the flagged classification and so is equivalent to a repeat of the private search | Held: Government learned new, critical information beyond the CyberTip; viewing exceeded antecedent private search. |
| Whether an automated, non‑human provider scan (hashing) fully frustrates a user’s expectation of privacy in a file | Wilson: A hash label is not equivalent to human viewing—the content remained unseen and privacy interests persisted | Government: The automatic identification and report sufficiently frustrated privacy so police could permissibly view | Held: Hash match alone did not eliminate Wilson’s privacy interest because no human at Google viewed his specific files; warrant required. |
Key Cases Cited
- Burdeau v. McDowell, 256 U.S. 465 (private searches by non‑government actors are generally outside Fourth Amendment constraints)
- Coolidge v. New Hampshire, 403 U.S. 443 (evidence turned over to police by private party acting on own initiative is not automatically governmental search; inquiry into agency)
- Walter v. United States, 447 U.S. 649 (plurality opinion: government exceeded scope where private party had not viewed content and government did)
- United States v. Jacobsen, 466 U.S. 109 (private‑search doctrine permits government to repeat private search only if government does not exceed scope of private search)
- United States v. Tosti, 733 F.3d 816 (9th Cir.) (distinguishing enlarging thumbnails that private party had viewed from new government intrusions)
- Carpenter v. United States, 138 S. Ct. 2206 (Supreme Court caution about mechanically applying third‑party doctrines in the digital age)
- United States v. Ackerman, 831 F.3d 1292 (10th Cir.) (addressing NCMEC/provider forwarding and whether government exceeded private search)