The FBI and other police agencies don’t need a search warrant to track the locations of Americans’ cell phones, a federal appeals court ruled on Tuesday in a precedent-setting decision.
In the first decision of its kind, a Philadelphia appeals court agreed with the Obama administration that no search warrant–signed by a judge based on a belief that there was probable cause to suspect criminal activity–was necessary for police to obtain logs showing where a cell phone user had traveled.
A three-judge panel of the Third Circuit said (PDF) tracking cell phones “does not require the traditional probable-cause determination” enshrined in the Fourth Amendment, which prohibits government agencies from conducting “unreasonable” searches. The court’s decision, however, was focused on which federal privacy statutes apply.
But the panel sided with civil-liberties groups on an important point: it agreed that, in at least some cases, judges may require investigators to obtain a search warrant. That is, however, “an option to be used sparingly,” the court said.