Electronic surveillance

What is the future of privacy, surveillance and policing technologies under Trump?

Law enforcement agencies say Stingray technology helps them catch suspected criminals -- and it does. But privacy advocates fear the technology's ability to collect nearby cellphone owners' data without their permission or knowledge -- and often, without a warrant -- compromises Fourth Amendment rights.

Federal authorities have said the devices they use are not configured to collect the content of communications, but the capabilities of the technology aren't clear. That's partly because federal authorities have shrouded cell site simulators in mystery, sometimes dropping cases against criminal suspects rather than reveal their policing methods and agreements with private cell site simulator companies that swear the government to product secrecy in contracts.

The ability to put the warrant requirement "through the shredder" at any moment is why policy is an insufficient safeguard, said Matthew Feeney, policy analyst at the Cato Institute, a libertarian think tank.