The FBI claims that it doesn't need a warrant to use so-called Stingray cell-phone tracking technology in public spaces, according to two US Senators raising privacy concerns over use of the devices.
Stingrays and similar devices intercept data by emulating a cell phone tower, say privacy groups. With the briefcase-size technology, police can identify and locate cell phone users in a general area or search for a specific person while also vacuuming up metadata from phones.
The FBI recently settled on a new policy surrounding the use of Stingrays and similar technology that requires agents to obtain a warrant before using the technology in a criminal investigation. However, the policy includes such broad exceptions that privacy advocates worry they do practically nothing to protect citizens' Fourth Amendment rights.
The new policy was first revealed by former Senate Judiciary Committee Chairman Patrick Leahy and the then ranking Republican on the committee, Chuck Grassley—who has since become chairman—in a letter to the Justice Department and Department of Homeland Security released at the end of December.
In the letter, Leahy and Grassley question whether law enforcement agencies using cell-phone-tracking technology "have adequately considered the privacy interests of other individuals who are not targets of the inception, but whose
information is nevertheless being collected when these devices are used."
The Wall Street Journal reported in November that the US Marshals Service was using cell-phone-tracking technology in small aircraft to search for criminal suspects, sweeping up thousands of other cell phone signals in the process.
Law enforcement agencies purchase Stingrays and similar devices—technically called International Mobile Subscriber Identity catchers—through federal grants under the auspices of anti-terrorism operations. Police say the technology can also be used for search-and-rescue operations, in kidnapping situations, and disaster response.
According to Leahy and Grassley, the FBI's new policy contains an exception for "cases that pose an imminent danger to public safety, cases that involve a fugitive, or cases in which the technology is used in public places or other locations at which the FBI deems there is no reasonable expectation of privacy."
Hanni Fakhoury, an attorney with the Electronic Frontier Foundation, said in a statement to VICE that it "seems that a carve out to allow the FBI to use an IMSI catcher in public without a warrant is an exception that swallows the rule."
Fakhoury said the FBI's new policy is "a good first step towards transparency, but there need to be a lot more information made public about how these devices are used.
"First, what was happening before the change in policy?" Fakhoury continued. "If the new policy requires the FBI to get a warrant to use the device but has an exception for when the device is in public use, does that mean the feds were using IMSI catchers to capture signals emanating from the home, a place clearly protected by the Fourth Amendment? Second, what is the requirement for FBI's use of these devices in public places, which is presumably where the bulk of these devices are used?"
Leahy and Grassley are pressing the Justice Department for more details on the privacy implications of the technology.
"The Judiciary Committee needs a broader understanding of the full range of law enforcement agencies that use this technology, the policies in place to protect the privacy interests of those whose information might be collected using these devices, and the legal process that DOJ and DHS entities seek prior to using them," Leahy and Grassley wrote in their letter to Attorney General Eric Holder and DHS Secretary Jeh Johnson.
Reports of police departments using Stingrays first surfaced in December 2013, when USA Today reported that cell phone surveillance technology originally designed for the US military was finding its way into state and local police departments across the country.
Since that report, the ACLU has unearthed public records showing police departments and federal law enforcement in 19 states and the District of Columbia are using IMSI catchers.
Transparency groups and news organizations trying to dig up more information on Stingrays have been stymied by an aggressive effort from federal agents, local police departments, and the company that manufactures the devices.
Earlier this year in Sarasota, Florida, the US Marshals Service confiscated records on Stingray surveillance from a courthouse just hours before the records were due to be handed over to the ACLU.
In September, a public records request revealed state and local police must sign a non-disclosure agreement with the FBI, keeping details of the devices secret.
Prosecutors in Baltimore went so far as to toss key evidence in a case rather than reveal details of how police used a Stingray to track the defendant.
The FBI and DHS did not immediately respond to requests for comment. In a statement to VICE, the Justice Department said only that it is reviewing Leahy and Grassley's letter, which calls for a response to their concerns by the end of the month.
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