Electronic surveillance

Stingray documents offer rare insight into police and FBI surveillance

Court documents ordered released by a judge in Oakland, California, have revealed rare insights into how local police and the FBI use a sophisticated surveillance device known as Stingray.

Stingray, manufactured by the Delaware-based Harris Corporation, is one of a class of devices known as “cell site simulators” or “IMSI-catchers”. About the size of a suitcase, they work by pretending to be a cellphone tower in order to strip metadata and in some cases phone content and data from nearby devices tricked into connecting to it.

Despite the fact that the devices are also capable of listening to phone calls, in many cases they still do not require a warrant to use, instead requiring a much lower-level authorisation known as a “trap-and-trace”, a court order designed in the era of the rotary phone.