US law enforcement sought mobile user data more than 1.3 million times in 2011

Federal, state and local law enforcement agencies in the US made more than 1.3 million requests for cellphone records in 2011, according to carriers' responses to a congressman's investigation

Federal, state and local law enforcement agencies in the US made more than 1.3 million requests for mobile phone records in 2011, according to carriers' responses to a congressman's investigation.

Those requests included ones seeking location data and the contents of text messages as well as wiretaps, according to Ed Markey of Massachusetts, who wrote to carriers in May to ask them about what law enforcement had sought from them. Some agencies also requested "cell tower dumps" to collect the phone numbers of all mobile subscribers who connected to a certain cell tower during a particular time.

The number of requests also appears to be rising, according to responses from carriers. Verizon Wireless said the number had grown by 15 percent per year over the past five years. T-Mobile estimated they were going up by between 12 percent and 16 percent.

Markey said he wrote to the phone companies after a New York Times article earlier this year said law enforcement was making routine data requests, sometimes with little oversight by courts. Markey, a Democrat who is co-chairman of the Congressional Bi-Partisan Privacy Caucus, has been involved in mobile privacy issues before. In January, he proposed a bill that would force carriers to tell consumers about any tracking or monitoring software installed in their cellphones.

The figure of 1.3 million requests in 2011 actually understates the case because T-Mobile, while reporting a rise in information requests, did not tell Markey how many requests it had received. The numbers were compiled from responses by Verizon, AT&T, Sprint Nextel and five smaller carriers: U.S. Cellular, Leap Wireless, MetroPCS, C Spire Wireless and TracFone Wireless.

Carriers said they respond only to legally proper requests, which can require subpoenas or court orders. The major carriers said they have dedicated staffs to handle such requests and are usually reimbursed by law enforcement for that work. AT&T, for example, said it had about 100 employees working full time on this area. But the carriers said they don't market their data-gathering capabilities to law enforcement agencies.