Supreme Court: Government needs warrant to access people's cell phone location information

Carpenter v. United States

(Alex Wong/Getty Images)

WASHINGTON – A Supreme Court ruling just made it significantly harder for the government to access your cellphone location information.

In a 5-4 ruling in Carpenter v. United States, the U.S. Supreme Court said the government typically will need a warrant if it wants to gain access to people's cellphone location information.

However, the ruling makes it possible for police officers to acquire cellphone location information without a warrant.

“We decline to grant the state unrestricted access to a wireless carrier’s database of physical location information,” Chief Justice John Roberts wrote in the court's majority opinion. “In light of the deeply revealing nature of CSLI (cell site location information), its depth, breadth, and comprehensive reach, and the inescapable and automatic nature of its collection, the fact that such information is gathered by a third party does not make it any less deserving of Fourth Amendment protection.”

Senior Associate Justice Anthony Kennedy, who wrote a dissenting opinion, argues the collection of cellphone location information should be allowed because "the data is less precise than GPS information."

This case dates back to 2011, when the government gained months' worth of cellphone location records from cell phone service providers for suspects in a Detroit robbery investigation.

The records for Timothy Carpenter, one of the suspects in the robbery, showed 127 days worth of data, including 12,898 different locations. He was then convicted, in part, because of the evidence from his cellphone location.

Carpenter then appealed, only to be unsuccessful in a 2-1 vote that ruled no warrant is required under the Fourth Amendment.

"Given the increasing use of new forms of electronic surveillance, it's important now more than ever that the Supreme Court steps in to push back against police overreach and clarify the protections of the Fourth Amendment," said Detroit attorney Harold Gurewitz, who represented Carpenter alongside the ACLU.