Coburn said the U.S. Supreme Court has already ruled that information about phone calls made from one number to another — the kind of records that phone companies send to customers in billing statements — is not protected from scrutiny by law enforcement.
Intelligence agencies need that data to connect the dots and they need to get it en masse because the phone carriers destroy it after a certain amount of time, Coburn said. If the intelligence agencies want to pursue more specific information, he said, they have to get a warrant and show other information to a Foreign Intelligence Surveillance Act court about their suspicions, he said.
The programs have stopped numerous terrorist acts, Coburn said, and the exposure in the past week will allow terrorists to change the way they communicate to avoid detection.
“Here's the option: lots more successful attacks, not just here but around the world,” Coburn said.
Coburn acknowledged the legitimacy of fears that revelations last week about data collection may only be the tip of the iceberg and that government agencies may not always adhere to the law or the U.S. Constitution.
Still, he said, the surveillance systems used by the intelligence agencies require constant oversight by the FISA court.