Supreme Court limits law enforcement use of geofence warrants

On Monday, the U.S. Supreme Court issued a 6-3 ruling limiting the law enforcement use of geofence search warrants—requests for the location data of all users within a specific geographic area. The decision establishes that authorities must obtain a search warrant when asking technology companies for the location data of their users. The ruling is likely to have broad ramifications for privacy rights and law enforcement across the United States.

In its decision, the U.S. top court affirmed that “an individual has a reasonable expectation of privacy in his cell-phone location information.” This ruling effectively applies the 4th Amendment—the US constitutional protection against unreasonable searches—to digital location history collected by companies from their users’ cellphones. The court addressed the “third-party doctrine,” which is a legal principle stating people have no expectation of privacy for data shared with third parties. It argued that users do not willingly share their location data with a company like Google simply by using its services, meaning this doctrine does not apply to geofence data.

The legal battle centers on the case Chatrie v. United States. The defendant, Okello Chatrie, accused the government of using evidence during his trial for bank robbery collected by an unconstitutional search warrant. His legal counsel argued that geofence warrants allow investigators to “search first and develop suspicions later.” Critics of these tools argue that these oft-called “reverse” search warrants are unconstitutional because they are inherently overboard and include innocent people’s data.

The decision does not stop law enforcement from getting historical cellphone location data, but it establishes that authorities must show probable cause—the legal standard required to justify a search warrant—to obtain this information. This change directly impacts how technology companies handle law enforcement demands for user location history. Google, which is frequently targeted by geofence warrants, is affected alongside other companies that receive these warrants on a regular basis, including Microsoft, Uber, and Yahoo.

Why it matters

This ruling establishes that the 4th Amendment applies to digital location data, forcing law enforcement to meet the probable cause standard rather than relying on broad, “reverse” search warrants.