Only a small fraction of law enforcement agencies in the United States obtain a warrant before tracking the cell phones of suspects and persons of interest. This is due, in part, to the fact that courts have struggled to keep pace with a changing technological landscape. Indeed, courts around the country have issued a disparate array of holdings on the issue of warrantless cell phone tracking. This lack of judicial uniformity has led to confusion for both law enforcement agencies and the public alike. In order to protect reasonable expectations of privacy in the twenty-first century, Congress should pass legislation requiring law-enforcement agencies to obtain a warrant based upon probable cause before they can track a cell phone except in a limited set of time-sensitive situations and emergencies. This Issue Brief describes the technology police use to track cell phones, discusses the need for federal legislation, concludes that current Fourth Amendment jurisprudence is inadequate to address cell phone tracking, analyzes two bills dealing with “geolocation information” privacy that legislators have introduced in Congress, and ultimately concludes that one of those bills is superior to the other.
Stephen Wagner, Stopping Police in Their Tracks: Protecting Cellular Location Information Privacy in the Twenty-First Century, 12 Duke Law & Technology Review 200-218 (2014)