From The Hill

Local police were told by the FBI to keep quiet about their use of a controversial surveillance device that tracked people’s cellphones, according to a newly disclosed document.

The StingRay devices, sometimes known as “cell site simulators,” mimic cellphone towers to send out signals and trick phones into relaying back information about their location and other data.T

Police departments can buy the trackers from the Florida-based Harris Corporation as long as they coordinate with the FBI ahead of time, a requirement set by the Federal Communications Commission (FCC), according to a heavily redacted December 2012 letter sent by the FBI to the police department in Tacoma, Wash.

The letter, revealed on Monday by Muck Rock, shows that the federal agency requires local police to complete a non-disclosure agreement “prior to the acquisition and use of the equipment/technology authorized by the FCC.” 

Transparency activist Phil Mocek first obtained the 2012 letter by filing a request under the Freedom of Information Act.

Four of the letter’s six pages are entirely blacked out, obscuring the details of the non-disclosure agreement.

The FBI has used the controversial StingRay technology since at least 1995, according to the Electronic Privacy Information Center, over the objections of privacy and civil liberties organizations.

According to the American Civil Liberties Union, at least 43 agencies in 18 states own the StingRays.

Rep. Alan Grayson (D-Fla.) raised concerns about the technology earlier this summer, prompting the FCC to set up a task force to look into whether criminals and spies might also be using the cellphone tracking technology.

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