The Department of Homeland Security has a new, more constitutional policy for cell-site simulators, also known as Stingrays. Rolled out today, the new policy follows in the footsteps of the previously announced Justice Department policy, requiring explicit warrants for the deployment of the technology, except in exceptions already made by the Fourth Amendment or "exigent circumstances" like threats to human life or destruction of evidence.
"As with any law enforcement capability, the Department of Homeland Security must use cell-site simulators in a manner that is consistent with the requirements and protections of the Constitution, including the Fourth Amendment," the policy reads. It's one of the few public acknowledgements that DHS is using the technology, which has remained shrouded secrecy despite being in use for more than 10 years.
Cell-site simulators are most often used to locate mobile devices with a specific phone number. By masquerading as a cell tower, the device can detect the phone numbers of any phone in range, and triangulate from there to determine the specific location of the phone in question. Still, the devices have drawn criticism from civil liberties groups over indiscriminate data collection, often leading to broad cell-service disruptions. In one program reported by The Wall Street Journal, the US Marshals flew over major cities with the devices, collecting data from tens of thousands of phones so as to locate a single fugitive.
As with the Justice Department policy, not everyone is convinced the new guidelines are strong enough. "Although getting a warrant in some investigations is better than getting a warrant in none, the DHS guidance is riddled with loopholes and exceptions," said ACLU counsel Neema Singh Guliani in a statement. "Congress needs to pass legislation to ensure that the use of these and other location tracking technologies respect the Fourth Amendment."
10/21 3:00PM ET: Updated to include ACLU statement.