Should the government be able to track your movements based on cell phone records, without evidence of criminal wrongdoing?
A legal showdown on the closely watched issue unfolded Friday in a federal appeals court in Philadelphia, as the Justice Department battled electronic privacy groups.
The Justice Department wants to get the cell-phone location information without showing probable cause of a crime. Opponents say the data could show when someone visits a church, medical clinic or political rally.
Appellate Judge Dolores Sloviter wondered aloud what a rogue government might do with such information.
The appeal stems from a Pittsburgh drug-trafficking case. The judges did not indicate when they would rule.