Electronic surveillance

New rules require feds to get warrant for cell phone surveillance

Federal law enforcement agencies will have to be more transparent about their use of cell-phone surveillance technology to track criminal suspects, according to a new policy released Thursday by the US Department of Justice.

The devices, called cell site simulators for the way they get nearby mobile phones to reveal their locations, are known for sweeping up large swaths of data on everyday people as part of criminal investigations. The new rules require federal agencies such as the FBI, US Marshals Service, and Drug Enforcement Administration to specify in a warrant request how the technology will be used and the safeguards that will be employed to protect the data of passersby who might unintentionally get caught in the surveillance.