Washington state will require a warrant for Stingray cell-phone tracking

On Monday, Washington state passed a new law requiring police to get a warrant before they use cell-site simulator tracking devices, known commonly as Stingrays. The devices have been widely deployed by law enforcement groups throughout the country but kept largely secret thanks to non-disclosure agreements and parallel construction techniques. The new Washington state law will be one of the most aggressive anti-tracking measures in the nation, although Virginia and Minnesota have adopted similar measures. It will also have an immediate effect on the Tacoma Police Department, which has been using a Stingray device in 2008.
According to The News Tribune of Tacoma, Washington, portions of Washington's new law were written by Daniel Rigmaiden, who was apprehended by the FBI in 2008 through the use of a Stingray device and has become an active advocate against the devices in the years since. Stingray devices work by impersonating a 2G cell phone tower, which can connect to phones without authentication. From there, the devices can pull location and basic identification data, and potentially even calls and text messages. They've been widely adopted by both federal agencies and local police departments alike. Baltimore police have used Stingray devices more than 4,000 times, according to court testimony, and the US Marshals service uses the same interceptors in low-flying planes to locate fugitives.
Federal agencies have recently attempted to scale back the secrecy surrounding Stingrays, but they remain largely undisclosed. Earlier this month, the Justice Department began a full review of how the devices are being used by law enforcement, which may result in further disclosures later in the year.