When the media and members of Congress say the NSA spies on Americans, what they really mean is that the FBI helps the NSA do it, providing a technical and legal infrastructure that permits the NSA, which by law collects foreign intelligence, to operate on U.S. soil. It’s the FBI, a domestic U.S. law enforcement agency, that collects digital information from at least nine American technology companies as part of the NSA’s Prism system. It was the FBI that petitioned the Foreign Intelligence Surveillance Court to order Verizon Business Network Services, one of the United States’ biggest telecom carriers for corporations, to hand over the call records of millions of its customers to the NSA.
And later on in three-pager (DITU is the name of the internal FBI division):
The NSA is the most frequent requester of the DITU’s services, sources said. There is a direct fiber-optic connection between Quantico and the agency’s headquarters at Fort Meade, Maryland; data can be moved there instantly. From the companies’ perspective, it doesn’t much matter where the information ends up, so long as the government shows up with a lawful order to get it.
This is the first time I recall hearing about the FBI involvement — but I have been reading and not reading a lot of articles lately.