SurveillanceNew cell phone surveillance method raises privacy concerns

Published 1 November 2012

The FBI is using a new method to access cell phone customer data,butthe American Civil Liberties Union (ACLU) contends that the method is overly invasive

The FBI is using a new method to access cell phone customer data,butthe American Civil Liberties Union (ACLU) contends that the method is overly invasive.

The method,known as “stingrays,” uses a person’s international mobile subscriber identity (IMSI) secretly totrack someone’s location using stingray devices, known as IMSI catchers. The catcher mimics a cell phone tower, but stingrays track the locations of all mobile devices in a given area,including those whichare not being targeted.

NBC reports that abig reason this scares privacy groups is that an IMSI catcher can be built at home for about $1,500, exposinga weakness in cell phone security to which most consumers areoblivious.

In 2010 a communications expert was able to make an IMSI catcher and thirty cell phones in the room attempted to connect to the make-shift tower. Anyone who made a call while connected to the stingray received a message saying that their call was being recorded.

On 19 October, a friend-of-the-court brief,filed with the U.S. District Court of Arizona by the Electronic Frontier Foundation in San Francisco and the American Civil Liberties Union of Northern California,argued that stingrays are “highly intrusive and indiscriminate,” and claimed government investigators attempted to utilize them while giving Judge Richard Seeborg only a few details about how powerfulstingrays can be.

“The government prevented the court from making an informed determination on the warrant application,” Linda Lye, staff attorney for the ACLU of Northern California,told the court. “Maybe the court would have said, ‘No, I’m not going to grant this at all because of the impact on third parties.’ Maybe the court would have said, ‘OK, you can do this, but let’s follow these safeguards and procedures to make sure that third-party privacy is protected.”

Hanni Fakhoury, a staff attorney for the Electronic Frontier Foundation,told the court that law enforcement deceived the courts in the warrants.

“If you read the warrant affidavit, it has absolutely zero mention at all of IMSI catchers and stingrays or fake cell phone towers or any explanation of the technology,” Fakhoury told the court.  “Courts are busy, judges are busy; they rely on the government in good faith to explain what they’re doing.”

Earlier this year a federal judge in Texas denied DEA investigators an application to use a stingray, once he understood the technology.

“They did not address what the government would do with the cell phone numbers and other information concerning seemingly innocent cell phone users whose information was recorded by the equipment,” Magistrate Judge Brian Owsley wrote in June. “While these various issues were discussed at the hearing, the government did not have specific answers to these questions. Moreover, neither the special agent nor the assistant United States attorney appeared to understand the technology very well.”

NBC notes that the U.S. attorney’s office in Phoenix did not comment on the most recent case involving stingrays. Prosecutorsstated in a 20 August filing that they only needed to show how a communications device can show evidence of criminal activity, but are not required to show what method would be used to get the information.

“Defendant was perpetrating a multi-million dollar tax fraud scheme, and he hid his tracks through the use of encrypted emails, money mules, layers of false identities, forged documents, forged identification cards, and botnets and/or proxies,” the filing reads. “ … The alleged inconvenience and intrusiveness of the aircard location operation (which went undetected by an individual who appeared to spend a significant portion of every day seeking to avoid detection or identification) was reasonable under the circumstances.”