Law Enforcement’s Secret “Super Search Engine” Amasses Trillions of Phone Records for Decades

EFF Fights For More Disclosure About Hemisphere Program

Although the government still hides too much information about a secret telephone records surveillance program known as Hemisphere, we have learned through EFF’s Freedom of Information Act (FOIA) lawsuits that police tout the massive database of private calls as “Google on Steroids” [pdf].

Hemisphere, which AT&T operates on behalf of federal, state, and local law enforcement, contains trillions of domestic and international phone call records dating back to 1987. AT&T adds roughly four billion phone records to Hemisphere each day [.pptx], including calls from non-AT&T customers that pass through the company’s switches.

The Drug Enforcement Agency (DEA) and other federal, state and local police use Hemisphere to not only track when and who someone is calling, but to perform complicated traffic analysis that can dynamically map people’s social networks and physical locations. This even includes knowing when someone changes their phone number.

And federal officials often do it without first getting permission from a judge.

Indeed, Hemisphere was designed to be extremely secret, with police instructed to do everything possible to make sure the program never appeared in the public record. After using Hemisphere to obtain private information about someone, police usually cover up their use of Hemisphere by later obtaining targeted data about suspects from phone providers through traditional subpoenas, a process the police call “parallel construction” and that EFF calls “evidence laundering.”