Privacy advocates and concerned citizens don’t just have to worry about the National Security Agency (NSA) anymore.
Local police are increasingly tracking and gathering data from people’s cellphones in what they say is an effort to fight crime and terrorism. Public records obtained by USA Today, Gannett newspapers, and TV stations tell the full picture: New technology , including mobile devices that can access cellphone data in real time, allow local and state police to capture information about cell users, whether or not they are under investigation. The records come from 125 police agencies in 33 states.
One of the key pieces of technology used by at least 25 police departments is called the Stingray. It is a suitcase-sized device that acts as a fake cell tower. Usually installed in a vehicle for mobility, the device tricks nearby phones into connecting and giving data to police, USA Today reported. In some states, any local police department can get its hands on a Stingray via state surveillance units. Most of the purchases of Stingrays, which can run $400,000 each, are funded by the federal government via anti-terror grants.
Police also use a tactic called a “tower dump,” which allows them to obtain data about the activity, location and identity of any phone that connects to targeted cellphone towers over what is usually a one-or-two-hour timespan, according to USA Today. A dump typically covers multiple towers and wireless providers and can get information from thousands of phones.
Thirty-six police agencies would not say if they’ve used a Stingray or tower dumps, arguing that criminals or terrorists could use that information to thwart law enforcement efforts.
According to an investigation by the Indianapolis Star and USA Today, police in some cities have used cellphone data collection for matters not as urgent as terrorism or major crimes.
A South Carolina sheriff, for example, got cellphone data  from multiple people to investigate a string of car burglaries that included the theft of guns from the sheriff’s SUV. And in Miami, police told the city council they would collect data to track protesters at a world trade event.
Organizations like the Electronic Privacy Information Center (EPIC) and the American Civil Liberties Union told USA Today the fact that even small police departments can easily and quickly grab so much phone data raises questions about erosion of privacy and Fourth Amendment safeguards against unreasonable search and seizure.
“I don’t think that these devices should never be used, but at the same time, you should clearly be getting a warrant,” said Alan Butler of EPIC.
Gerry Lanosga of the Indiana Coalition for Open Government, a group that advocates for government transparency, told the Star that police should have to provide at least some information about how the data collection technology is being used.
“I think the public has a right to know some details about that program,” he said.
Law enforcement in other parts of the country (Indiana police would not discuss the matter) only need a court order, not a warrant, to obtain phone data, the Star said. The scrutiny for a court order is much lighter than for a warrant; police only need to show the data collection would aid their investigation to obtain a court order, while a warrant would need police to show probable cause—a legal term meaning belief that a crime has occurred.
Lanosga said Indiana police should publicly address concerns related to privacy and explain the checks and balances they have in place to protect any data they collect.
“What sort of reassurances can the agency make to those people their data is being destroyed, not maintained indefinitely, not abused for any purpose?” he said.