US Supreme Court Rules Location Data Protected by Fourth Amendment in Chatrie v. United States

In the decision Chatrie v. United States, the US Supreme Court ruled that individuals have a reasonable expectation of privacy in location data that reveals physical movements. The Court held that even short-term surveillance of these movements constitutes a search subject to the Fourth Amendment, significantly expanding the privacy precedent set in Carpenter v. United States (2018).

What Changed

The ruling specifically addresses the legality of "geofence warrants"—a form of dragnet surveillance where law enforcement compels technology companies to provide location data for every electronic device within a specific geographic radius during a set timeframe. The Court determined that such warrants, which do not name a specific suspect or device, infringe upon constitutional protections.

Crucially, the Court recognized that records generated by mobile applications—which users necessarily share with third-party tech companies—are the "own" records of the user and require Fourth Amendment protection. This applies regardless of whether the data includes location, emails, documents, photographs, or calendars.

Who Is Affected

• Technology Companies: Providers like Google, who are frequently the targets of geofence warrants, must navigate these heightened constitutional requirements.
• Law Enforcement Agencies: Police departments can no longer utilize suspicionless geofence warrants to vacuum up data from innocent bystanders in the vicinity of a crime.
• Data Brokers: The decision sets a precedent that may impact how law enforcement accesses aggregated location data purchased from third-party brokers.
• Mobile App Developers: The ruling clarifies that data generated by various apps is subject to Fourth Amendment protections because users reasonably view such data as their own.

Operational Impact

The decision clarifies that location data is a user's "personal property," as noted in Justice Gorsuch's concurring opinion. This means that the Fourth Amendment must protect more than just the data generated by the act of carrying a phone; it must protect the substantive data contained within the device's applications. While the case now returns to the Fourth Circuit to address specific questions regarding "good faith" and the reasonableness of the particular warrant in question, the legal standard for digital surveillance has been fundamentally raised.

Legal departments and compliance officers should monitor how lower courts apply this ruling to other forms of suspicionless digital searches, such as "cell tower dumps."

Source: Victory! Supreme Court Says Constitution Protects People's Location Data
Domain: eff.org