FAC suit against San Diego yields previously secret records on police use of invasive cell phone surveillance tool

The Stingray is a controversial cell phone surveillance tool used by police departments in major US cities, including Los Angeles, San Francisco, Oakland, San Jose and San Diego.  Also known as an “IMSI catcher,” the Stingray operates by mimicking a cell phone tower, which causes cell phones in the vicinity to transmit information revealing their owners and the phones’ exact location.

In 2015 FAC filed a public records suit against the San Diego Police Department for access to records about the department’s use of the Stingray. Records released recently as part of that lawsuit reveal the complete text of previously-secret nondisclosure agreements that San Diego and other Stingray-equipped cities have signed with both the FBI and with the Harris Corp., the Florida-based manufacturer of the Stingray.

The nondisclosure agreements, which we have published here, forbid the release of virtually any information about the capabilities and functioning of Stingray. So restrictive are the agreements that the San Diego PD (and, presumably, other police departments that have signed similar agreements) are required, at the FBI’s direction, to pull the plug on criminal prosecutions that rely on Stingray-derived evidence and which risk disclosure of sensitive information about the Stingray.

Other highlights from the San Diego PD’s disclosure of Stingray information to FAC:

—- San Diego paid some $365,000 for its Stingray technology, according to partially redacted purchase orders.

—- The Stingray is configured for US police departments to capture only the unique identifier information of the cell phone user and the precise location of a specific cell phone. However, the device has the ability to capture phone conversations and the content of text messages.

—-Stingray’s locating of cell phones is highly accurate—-within 2 meters of the phone’s actual location, according to a stipulation signed by the SDPD for the FAC lawsuit. This is significantly more accurate than the information available to police from cell phone providers like Verizon and AT&T.

The use of Stingrays has been criticized by privacy advocates because they cast a broad net. Although police, when deploying a Stingray, may be searching for a single cell phone associated with a single suspect, the Stingray nonetheless receives identifying and locating signals from all other cell phones in the vicinity, regardless of the fact that the phones’ owners are not suspected of committing any crime.

Despite these privacy concerns, it appears that San Diego PD, when requesting a search warrant for use of the Stingray, does not reveal to the judge that the Stingray (or IMSI catcher) is the intended surveillance tool. The San Diego PD’s model warrant application, disclosed to FAC in the ongoing lawsuit, describes various other phone tracking and surveillance tools available to police and covered by the warrant application. But there is no mention of the Stingray (or IMSI catcher or other names for the cell tracking technology).

Obviously, if a judge is not made aware that a requested search warrant is for use of a Stingray, the judge will not realize that the proposed search will include all cell phones (and their owners)  in the vicinity of the Stingray deployment—-not just the cell phone of the person for whom the police have shown “probable cause.” The San Diego PD’s search warrant applications, unless clarified through other representations, mislead the judges to whom they are submitted.

That’s our view. Read the documents and decide for yourself.–PS