WASHINGTON — In the first public accounting of its kind, cellphone carriers reported that they responded to a startling 1.3 million demands for subscriber data last year from law enforcement agencies seeking text messages, caller locations and other information in the course of investigations.
The data, which come in response to a congressional inquiry, document an explosion in cellphone surveillance in the last five years, with wireless carriers turning over records thousands of times a day in response to police emergencies, court orders, law enforcement subpoenas and other requests.
The cellphone carriers reports also reveal a sometimes uneasy partnership with law enforcement agencies, with the carriers frequently rejecting demands that they considered legally questionable or unjustified. At least one carrier even referred some inappropriate requests to the FBI.
The information represents the first time data have been collected nationally on the frequency of cell surveillance by law enforcement. The volume of the requests reported by the carriers which most likely involve several million subscribers even surprised some officials who have closely followed the growth of cell surveillance.
I never expected it to be this massive, said Rep. Edward J. Markey, a Massachusetts Democrat who requested the data from nine carriers, including AT&T, Sprint, T-Mobile and Verizon, in response to an article in April in The New York Times on law enforcements expanded use of cell tracking. Markey, who is the co-chairman of the Bipartisan Congressional Privacy Caucus, made the carriers responses available to The Times.
While the cell companies did not break down the types of law enforcement agencies collecting the data, they made clear that the widened cell surveillance cut across various levels of government from run-of-the-mill street crimes handled by local police departments to financial crimes and intelligence investigations at the state and federal levels.
AT&T alone now responds to 230 emergency requests a day nationwide triple the number it fielded in 2007, the company told Markey. Law enforcement requests of all kinds have been rising quickly among the other carriers as well, with annual increases of between 12 percent and 16 percent in the last five years. Sprint led the way last year, reporting more than 500,000 law enforcement requests for data.
Under federal law, the carriers said they generally required a search warrant, a court order or a formal subpoena to release information about a subscriber. But in cases that law enforcement officials deem an emergency, a less formal request is often enough. Moreover, rapid technological changes in cellphones have blurred the lines on what is legally required to get data particularly the use of GPS systems to identify the location of cellphones.
As cell surveillance becomes a seemingly routine part of police work, Markey said in an interview that he worried that digital dragnets threatened to compromise the privacy of many customers. Theres a real danger weve already crossed the line, he said.
Markey and other Democrats are considering legislation that they say would more clearly draw the line between giving the authorities the technological tools they need and protecting the privacy of the public. With the rising prevalence of cellphones, officials at all levels of law enforcement say cell tracking represents a powerful tool to find suspects, follow leads, identify associates and cull information on a wide range of crimes.
At every crime scene, theres some type of mobile device, said Peter Modafferi, chief of detectives for the Rockland County district attorneys office in New York, who also works on investigative policies and operations with the International Association of Chiefs of Police. The need for the police to exploit that technology has grown tremendously, and its absolutely vital, he said in an interview.
As cell surveillance increased, warrants for wiretapping by federal and local officials eavesdropping on conversations declined 14 percent last year to 2,732, according to a recent report from the Administrative Office of the United States Courts.
The diverging numbers suggest that law enforcement officials are shifting away from wiretaps in favor of other forms of cell tracking that are generally less legally burdensome, less time consuming and less costly. (Most carriers reported charging agencies between $50 and $75 an hour for cellphone tower dumps.)
To handle the demands, most cell carriers reported employing large teams of in-house lawyers, data technicians, phone cloning specialists and others around the clock to take requests from law enforcement agencies, review the legality and provide the data.
But a number of carriers reported that as they sought to balance legitimate law enforcement needs against their customers privacy rights, they denied some data demands because they were judged to be overreaching or unauthorized under federal surveillance laws.
Sometimes, the carriers said, they determined that a true emergency did not exist. At other times, police agencies neglected to get the required court orders for surveillance measures, left subpoenas unsigned or failed to submit formal requests.
Requests from law enforcement officials to identify the location of a particular cellphone using GPS technology have caused particular confusion, carriers said. A Supreme Court ruling in January further muddled the issue when it found that the authorities should have obtained a search warrant before tracking a suspects movements by attaching a GPS unit to his car.
Law enforcement officials say the GPS technology built into many phones has proved particularly critical in responding to kidnappings, attempted suicides, shootings, cases of missing individuals and other emergencies. But Sprint and other carriers called on Congress to set clearer legal standards for turning over location data, particularly to resolve contradictions in the law.
While the carriers said they always required proper legal orders before turning over nonemergency information, their assurances were somewhat at odds with anecdotal evidence recently gathered by the American Civil Liberties Union from more than 200 law enforcement agencies nationwide.
Chris Calabrese, a lawyer for the ACLU, said he was concerned not only about officials gathering phone data on people with no real connection to crimes, but also about the agencies then keeping those records indefinitely in internal databases.
The standards really are all over the place, Calabrese said. Nobody is saying dont use these tools. What were saying is do it with consistent standards and in a way that recognizes that these are tools that really can impact peoples privacy.