The policy, as the agency wrote, “provides guidance and establishes common principles for the use of cell-site simulators across DHS.” The policy applies to the “use of cell-site simulator technology inside the United States in furtherance of criminal investigations,” the memorandum states.
Primarily, the policy hits on a required search warrant before operating a stingray device. In the past, the government has been derided for picking up innocent citizens' data while they're sharing public spaces with criminal investigation targets.
The majority of cases will require prosecutors to obtain a search warrant supported by probable cause; however, in exigent circumstances under the Fourth Amendment, such as situations where law enforcement's needs are “so compelling that they render a warrantless search objectively reasonable” the warrant requirement can be waved. Exceptional circumstances are also exempt from a mandatory warrant. These instances often occur when obtaining a search warrant is “impracticable,” such as when Secret Service agents are protecting the president.
As far as data collection, data must be deleted as soon as the target is identified and no less than once every 30 days.
The policy release was accompanied by a hearing at the U.S. House Committee on Oversight and Government Reform. The representatives asked for clarification from both DHS and the DOJ on their stingray use and rules.
When Rod Blum (R-Iowa) probed about how agents would be reprimanded if they didn't follow these policies, both the DOJ and DHS said individuals would be left to the agencies' idea of appropriate punishment, but employees would definitely be held accountable.
“As with any technology procedure within an agency if individuals violate their agency's orders they're accountable to their agencies and subject to discipline,” said Elana Tyrangiel, principal deputy assistant attorney general, Office of Legal Policy at DOJ.
To ensure their policies are followed, both agencies instated an auditing procedure with designated executive-level contacts serving as direct lines of contact.