The US Secret Service and Immigration and Customs Enforcement (ICE) agencies have failed to follow the law and official policy regarding the use of cell-site simulators, according to a government audit.
Cell-site simulators (CSS), also known as Stingrays or IMSI Catchers, are devices that serve as decoy cell towers. They’re used by law enforcement, intelligence services, and others to intercept metadata or communications, and triangulate a phone’s location. Essentially, your handset connects to the nearby tower, think it belongs to a telco, but in fact, it’s a temporary mast set up by the Feds to snoop on devices within range.
For years, these devices have elicited criticism from civil rights groups and legislators who argue that they violate Fourth Amendment protection against unreasonable search and seizure. The government insists it will only use this type of kit in line with existing rules and restrictions, but it appears that is not the case.
The Department of Homeland Security (DHS) Office of the Inspector General (OIG) looked at CSS deployment by the Secret Service and ICE and found, “Secret Service and ICE HSI [Homeland Security Investigations] did not always adhere to Federal statute and CSS policies when using CSS during investigations involving exigent circumstances.”
The OIG audit report [PDF] also found that “ICE HSI did not adhere to Department privacy policies and the applicable Federal privacy statute when using CSS.”
The audit was originally undertaken to look at how the agencies adhered to policies on cell-phone surveillance and commercial location-sharing