The US Supreme Court reversed a lower court ruling by a vote of 5-4 and struck a victory for privacy rights.
Carpenter v. United States is the first case about phone location data that the Supreme Court has ruled on. That makes it a landmark decision regarding how law enforcement agencies can use technology as they build cases. The court heard arguments in the case on Nov. 29.
The dispute dates back to a 2011 robbery in Detroit, after which police gathered months of phone location data from Timothy Carpenter’s phone provider. They pulled together 12,898 different locations from Carpenter, over 127 days.
The legal and privacy concern was that police gathered the four months’ worth of Carpenter’s digital footprints without a warrant. A Sixth Circuit Court of Appeals judge ruled that cellphone location data is not protected by the Fourth Amendment, which forbids unreasonable search and seizure, and therefore didn’t require a warrant.
Writing for the majority, Chief Justice Roberts noted that the searches were a 4th Amendment search.
“The government’s position fails to contend with the seismic shifts in digital technology that made possible the tracking of not only Carpenter’s location but also everyone else’s, not for a short period but for years and years,” he wrote.
Roberts said allowing government access to historical GPS data infringes on Carpenter’s Fourth Amendment protections and expectation of privacy, by providing law enforcement with an “all-encompassing record” of his whereabouts. He added that historical GPS data presents an “even greater privacy risk” than real-time GPS monitoring.
Before the trial took place, major tech companies, including Apple, Facebook and Google, filed a friend-of-the-court brief with the Supreme Court, urging the justices to make it harder for law enforcement officials to obtain individuals’ data without a warrant.
This is a major victory for privacy rights advocates and citizens in general. A warrant should be issued before law enforcement or other governmental agency are allowed to intrude into the private lives of the public.