Background
Eric Robert Johnson was convicted in the District of Massachusetts for possessing child pornography after the FBI used a law enforcement tool called Freenet Roundup to identify his IP address. The tool logged requests for illicit files sent by users on the Freenet peer-to-peer network. Johnson moved to suppress the evidence, arguing the government’s use of the tool violated the Fourth Amendment because he had an expectation of privacy in his anonymous activity.
The court’s reasoning
The court assumed without deciding that Johnson had a subjective expectation of privacy but found he failed to establish an objective one. The court held that Freenet is not a ubiquitous part of daily life like a cell phone and does not reveal the whole of a person’s physical movements. Because Johnson voluntarily operated in Opennet mode, he connected with strangers and exposed his IP address, which the platform warned was vulnerable to identification. The government’s use of Freenet Roundup merely allowed it to receive and log information that Johnson voluntarily transmitted to the public network, similar to an undercover officer participating in a transaction. The court distinguished this from Carpenter v. United States, noting that Freenet does not amass a detailed chronicle of a person’s physical presence.
Once frustration of the original expectation of privacy occurs, the Fourth Amendment does not prohibit governmental use of the now nonprivate information.
United States v. Ewing, 140 F.4th 1339, 1348 (11th Cir. 2025)
What it means going forward
The decision confirms that law enforcement may use modified peer-to-peer software to identify users who voluntarily transmit illicit content in public modes of the network without a warrant.