A powerful new surveillance tool being adopted by police departments across the country comes with an unusual requirement: To buy it, law enforcement officials must sign a nondisclosure agreement preventing them from saying almost anything about the technology.Any disclosure about the technology, which tracks cellphones and is often called StingRay, could allow criminals and terrorists to circumvent it, the F.B.I. has said in an affidavit. But the tool is adopted in such secrecy that communities are not always sure what they are buying or whether the technology could raise serious privacy concerns.
http://www.nytimes.com/2015/03/16/business/a-police-gadget-tracks-phones-shhh-its-secret.html
A Police Gadget Tracks Phones? Shhh! It’s Secret
A powerful new surveillance tool being adopted by police departments across the country comes with an unusual requirement: To buy it, law enforcement officials must sign a nondisclosure agreement preventing them from saying almost anything about the technology.