The government cannot search extended cell phone location records without a warrant, the Fourth Circuit ruled last Wednesday. Cell phone service providers routinely collect and record cell site location information, creating detailed reports of where a phone was and when. Should the government wish to look at that information over an extended time frame -- a phone's location over a 221-day period, for example -- it must obtain a valid warrant, the Fourth ruled.
The ruling, which has been praised by privacy advocates and civil liberties groups, creates a split with several other circuit courts. As commentators note, the issue raised is primed to end up before the Supreme Court in short order.