What has been vaguely described in multiple criminal cases as a “proven law enforcement technique” has lately come under increased scrutiny.

“Site cell simulators,” more widely known by their brand name StingRay, have been around for about 10 years. These controversial surveillance devices, which mimic cellphone towers, have been used by St. Louis police to pinpoint phones, down to the single room where a phone is located.

A StingRay detects every cellphone in a general area, not just the “target” phone. A major concern with StingRays is that the surveillance they provide can amount to a warrantless search. Police can drive around with the device, which is about as big as a suitcase, potentially gathering data from the target phone and bystanders’ phones.

Apparently, in an effort to keep judges, defense lawyers and the general public from scrutinizing the use of these devices, police in St. Louis have established a confidentiality agreement with the FBI. Before local police departments started using them, StingRays were used only by federal investigators.

Prosecutors are believed to have dropped criminal cases in order to prevent defense attorneys from analyzing the legality of the use of StingRays in criminal investigations.

When such a powerful surveillance tool is in the hands of law enforcement, it is crucial that appropriate search warrants are issued to limit the scope of the surveillance. Illegal searches happen far more often than people realize, and criminal charges resulting from illegal searches can be challenged and dismissed.

If you believe you are facing criminal charges based on an illegal search or seizure, then do not hesitate to contact a criminal defense attorney.