Telecommunications giant AT&T is selling access to customer data to local law enforcement in secret, new documents released on Monday reveal.



The program, called Hemisphere, was previously known only as a “partnership” between the company and the US Drug Enforcement Agency (DEA) for the purposes of counter-narcotics operations.



It accesses the trove of telephone metadata available to AT&T, who control a large proportion of America’s landline and cellphone infrastructure. Unlike other providers, who delete their stored metadata after a certain time, AT&T keeps information like call time, duration, and even location data on file for years, with records dating back to 2008.

But according to internal company documents revealed Monday by the Daily Beast, Hemisphere is being sold to local police departments and used to investigate everything from murder to Medicaid fraud, costing US taxpayers millions of dollars every year even while riding roughshod over privacy concerns.

Access to Hemisphere costs local police between $100,000 and more than $1m a year, the documents reveal, and its use requires just an administrative subpoena – a much lower judicial bar than a search warrant because it does not need to be issued by a judge.

Until Monday, Hemisphere’s use was kept secret from the public – and even from judges, defense attorneys and lawmakers – by an agreement between law enforcement and AT&T which means police must not risk disclosing its use in public or even in court.

This means that police take leads from Hemisphere, but then construct cases around that lead so that the program can be protected from scrutiny, a practice known as “parallel construction”, according to the Beast.

The revelations come as AT&T prepares for its controversial $85bn acquisition of Time Warner, a deal which has been widely attacked as being bad for consumers, with both presidential candidates speaking out against the merger.

Contacted for comment, Fletcher Cook, a spokesperson for AT&T, sent the Guardian the same statement they provided the Beast:



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.

Asked for further details, Cook did not respond.

The secrecy of Hemisphere echoes that which surrounds the use of the sophisticated surveillance devices known as Stingrays, or cell-site simulators, which are suitcase-sized devices which work by pretending to be cellphone towers in order to strip metadata and content from phones which connect to them.

In 2015, a Guardian investigation revealed that police departments had to sign a non-disclosure agreement with the FBI in order to use Stingray devices which said that police must hide the program’s use from defense lawyers and the public, even mandating that they abandon a case if they fear the program’s use might be revealed in court.

Nate Wessler, a staff attorney with the American Civil Liberties Union’s speech, privacy and technology project, said that, as with the Stingray agreement, “what is so disturbing about these documents is the lengths to which the company and law enforcement have gone to keep this secret”.

“The longer these kind of surveillance programs are kept from the public, the harder it is to ensure there are appropriate checks and balances in place,” Wessler said.

For Wessler, an instructive part of what the documents reveal is that while the program was apparently instigated as part of the war on drugs, “this data is being used for run-of-the-mill criminal investigation at a local level”.

“Once law enforcement has access to this kind of data it becomes a tremendously attractive tool for everything they do.”