AT&T runs a secret program called Project Hemisphere that that searches millions and millions of call records and analyzes cellular data to help law enforcement spy on Americans, according to documents obtained by The Daily Beast.

Police use the data to solve crimes by monitoring if specific cellular towers in the vicinity of wrongdoings picked up a known suspect’s cell phone. The surveillance project comes to light as the company is on the verge of acquiring Time Warner in one of the biggest media mergers in memory.

Law enforcement agencies pay from $100,000 to over $1 million a year for Hemisphere access, according to the Beast. Back in 2013, The New York Times called Hemisphere a partnership between AT&T and the government, but Daily Beast says it’s actually “a product AT&T developed, marketed, and sold at a cost of millions of dollars per year to taxpayers.”

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When TheWrap reached out to AT&T for comment, the telecommunications giant sent back a statement taking the position that the company is simply complying with the law.

“Like other communications companies, if a government agency seeks customer call records through a subpoena, court order or other mandatory legal process, we are required by law to provide this non-content information, such as the phone numbers and the date and time of calls,” a spokesperson said. “These types of legal demands are referenced in the law enforcement section of our Transparency Report.”

AT&T documents obtained by Daily Beast show that no warrant is required to access Hemisphere, but it does require a promise not to publicly disclose Hemisphere.

“Companies have to give this data to law enforcement upon request, if they have it. AT&T doesn’t have to data-mine its database to help police come up with new numbers to investigate,” ACLU technology policy analyst Christopher Soghoian told Daily Beast when explaining that all telecommunications companies are obligated to hand over data but AT&T has found a way to profit from it.

AT&T owns significant shares in both the landline and cell phone space, which allows the company to possess information that is used by at least 28 intelligence centers in America, according to the Beast.

One of the centers staffed with federal agents and local cops is the Los Angeles Regional Criminal Information Clearinghouse. Documents show that AT&T wants to keep Hemisphere a secret, but suspects and anyone charged with a crime have the right to know the evidence against them.

“The Government agency agrees not to use the data as evidence in any judicial or administrative proceedings unless there is no other available and admissible probative evidence,” documents obtained by the Beast said.