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The Drug Enforcement Agency can comb through roughly 26 years of phone records in their pursuit of big time drug dealers through a newly revealed partnership with AT&T to provide the law enforcement agency with real time access to an unprecedented amount of user information.

According to reports from The New York Times and ABC News, the DEA has been paying AT&T since 2007 to work directly with the High Intensity Drug Trafficking Areas program to offer access to every call that goes through the communications company's switchboard. The Hemisphere Project, an unclassified but "law enforcement sensitive" program, places an AT&T employee in four DEA offices across the country -- two in Los Angeles, one in Houston, one in Atlanta -- to assist federal and local officials working together to track down suspects. It gives the DEA access to records including phone numbers, time and duration of calls and the location where the call was made dating back 26 years -- all the way back to 1987. "Some four billion call records are added to the database every day," the Times explains, per training slides for AT&T employees that were released through FOIA requests.

The program is primarily used to track drug trafficking suspects who routinely switch phones or phone numbers to avoid detection from law enforcement. Drug dealers will use "burner phones" to make a small batch of calls to lieutenants in their operation before discarding the phone before police can track their behavior. The Hemisphere Project tries to work around that. ABC News does the best job explaining how law enforcement officials use the records to track major suspects:

Essentially, the program uses a suspect’s past phone calls to identify associates, and then uses those associates’ recent call patterns to identify the suspect’s new number. Subpoenas are obtained to proceed with each step.

The DEA's project gives them access to more user information than the phone records collected by the National Security Agency's surveillance programs. Their archives only go back five years because of restrictions imposed by the Patriot Act. But the Hemisphere Project doesn't collect and store data at DEA offices. The AT&T rep works to retrieve and deliver data "in real time," law enforcement sources told ABC News, from archives stored by the communications company. "Hemisphere results can be returned via email within an hour of the subpoenaed request," Hemisphere training materials say. "Hemisphere data contains roaming information that can identify the city and state at the time of the call."