On June 22, the U.S. Supreme Court ruled in favor of digital privacy. In a 5-4 decision, the justices said law enforcement needs a search warrant to obtain cellphone location data as evidence for trials, changing the way how police can use technology to build their cases.
Carpenter. V. United States is the first case regarding phone location information that the Supreme Court has ruled on. Timothy Carpenter was convicted in several armed robberies in Ohio and Michigan after law enforcement obtained his cellphone location history that pinned him to the scenes of the crimes. Law enforcement pulled together over 127 days’ worth of data from 12,898 different locations.
The lower courts ruled that cellphone location data isn’t protected by the Fourth Amendment and, therefore, didn’t require a warrant. However, Chief Justice John Roberts wrote the government’s searches of Carpenter’s phone records were considered a Fourth Amendment search since common surveillance law doesn't apply to the digital realm.
The court's liberal justices (all four of them) sided with Roberts. By contrast, the court’s other four conservatives did not.
This was the third decision that involved privacy in the digital world, ruling against police each time. In 2014, it ruled that law enforcement must obtain a warrant to search a person’s cellphone content when the user is arrested. Two years before that decision, the court said that a warrant is required to put a GPS tracking device on a vehicle.