Trickle down surveillance

Cell site simulators, also known as “stingrays,” are devices that trick cellphones into reporting their locations and identifying information. They do so by mimicking cellphone towers and sending out electronic cues that allow the police to enlist cellphones as tracking devices, thus revealing people’s movements with great precision. The equipment also sends intrusive electronic signals through the walls of private homes and offices, learning information about the locations and identities of phones inside. Initially the domain of the National Security Agency (NSA) and other intelligence agencies, the use of stingrays has trickled down to federal, state and local law enforcement. In one Florida case, a police officer explained in court that he “quite literally stood in front of every door and window” with his stingray to track the phones inside a large apartment complex.

Even when police are tracking a specific suspect, stingrays sweep up information about large numbers of bystanders who happen to be nearby; if stingrays yell out “Marco,” the mobile phones in the area reply, “Polo.” The result is that police gather the electronic serial numbers and other information about phones, as well as the direction and strength of each phone’s signal, allowing precise location tracking. Stingrays can also gather information about people’s communications, such as which phone numbers they call. Because we carry our cellphones with us virtually everywhere we go, stingrays can paint a precise picture of where we are and who we spend time with, including our location in a lover’s house, in a psychologist’s office or at a political protest.  

This sort of invasive surveillance raises serious questions about whether our tax dollars are funding violations of the U.S. Constitution’s Fourth Amendment. At a minimum, police should be required to go to a neutral judge, demonstrate probable cause and get a warrant before using stingrays, but many law enforcement agencies are not doing that. Instead, they seek permission using “pen register” and “trap and trace” statutes, which are based on a low legal standard and are designed to allow collection only of limited information about the numbers a phone dials or the numbers of incoming calls. Other agencies may not be going to a judge at all, or they may be concealing stingray use even when they do seek a court order.

The use of stingrays is murky and secretive, so it’s hard to tell how widespread it is. Over the past several months, the American Civil Liberties Union (ACLU) has submitted dozens of public records requests to state and local law enforcement agencies in Florida seeking information about which agencies own and use stingrays, how they use them, whether they have policies in place to restrict stingray use and protect bystanders’ privacy, and whether they get probable cause warrants from judges. The state’s practices were brought to our attention because of a Tallahassee case in which the cops secretly used a stingray without getting a warrant, but an appellate judge revealed at oral argument that local police had used the devices not only in that case but approximately 200 other times.

When we recently sent a records request to Florida’s Sarasota Police Department, it started off responding normally. It told us it had copies of court applications and orders authorizing use of stingray equipment, and invited a local representative of the ACLU down to take a look. Hours before the appointment, though, the police department canceled it, telling us that the U.S. Marshals Service (part of the Department of Justice) claimed ownership of the records because it had previously deputized the local detective who was storing the documents in his office. Then the marshals showed up at the local police station, seized the records and spirited them away to an unknown location — a blatant violation of state open-records laws.

What started out as a routine public records request has become a fight over the proper bounds of government secrecy and the importance of judicial oversight of police surveillance tactics.

The marshals’ action was extreme, but it fits into a broader pattern of secrecy surrounding stingray surveillance. In other cases around the country, the federal government has persuaded local police departments to invoke national security concerns in an attempt to prevent judges from ordering the release of basic information about stingray use. Stingray technology was originally developed for use by intelligence and military agencies; now the NSA’s surveillance tactics, and the secrecy shrouding them, have trickled down to local law enforcement with the help of the federal government.

In Tucson, Arizona, for example, the FBI has opposed a public records request to the local police by arguing that releasing information about stingrays to a journalist would violate the Arms Export Control Act. Similarly, in Tallahassee, the FBI tried to defeat an ACLU request for access to judicial records describing police use of stingrays in a local investigation by invoking counterterrorism concerns. In May, a judge rejected that argument out of hand, recognizing that information about regular criminal investigations cannot be kept secret merely because a federal agency might use similar equipment in unrelated national security investigations.

In other cases, police have tried to take a page from the CIA’s playbook by refusing even to confirm or deny whether they use stingrays. Some police departments even tried to keep records secret by pointing to a nondisclosure agreement they signed with the corporation that manufactures the devices or with an unnamed federal agency. It shouldn’t need to be said, but local cops aren’t by law allowed to sidestep public records statutes by entering into secret agreements with private corporations or outside agencies.

Despite this secrecy, we have been able to obtain significant pieces of information about stingray surveillance elsewhere: a new ACLU analysis of press reports and publicly available records reveals that at least 37 state and local law enforcement agencies in 15 states own stingray devices. From Anchorage, Alaska, to Alexandria, Virginia, local police are buying and using invasive surveillance gear in all kinds of local investigations. Other police departments are likely using stingrays in complete secret. This number also doesn’t include the many police departments that routinely borrow stingrays owned by the FBI, U.S. Marshals or state police. The Tallahassee Police Department has revealed, for example, that it has borrowed stingrays from the Florida Department of Law Enforcement more than 250 times since 2007. Numerous federal agencies own stingrays too, including the DEA, FBI, ATF, Secret Service and Immigration and Customs Enforcement. 

Why is the government trying so hard to hide records from the public? Law enforcement agencies contend that releasing information would hamper their ability to fight crime, but that argument doesn’t hold because we aren’t seeking confidential information about active investigations. Police shouldn’t be able to hide basic facts about what kinds of cases they use stingrays in and what protections are in place to guard against abuse.  

Government transparency is crucial because when the public and lawmakers have information about stingrays, real debate and effective privacy protections result. Take Michigan, where the Legislature recently held an oversight hearing to investigate a county sheriff’s use of stingray devices. Or Indiana and Utah, where legislatures have enacted laws that require police to get a warrant before tracking cellphones using stingrays or other means. In Minnesota, public revelation that the Hennepin County Sheriff’s Office wanted to buy a stingray several years ago led to robust debate at public county government meetings and passage of a law requiring that all future purchases of stingray equipment be explicitly approved by the county board. Government transparency leads to better policy and more robust protections of our privacy rights. That’s why the government’s reflexive secrecy around its use of stingrays is corrosive and detrimental to the public trust.