Shane Harris writes: With every fresh leak, the world learns more about the U.S. National Security Agency’s massive and controversial surveillance apparatus. Lost in the commotion has been the story of the NSA’s indispensable partner in its global spying operations: an obscure, clandestine unit of the Federal Bureau of Investigation that, even for a surveillance agency, keeps a low profile.
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.
But the FBI is no mere errand boy for the United States’ biggest intelligence agency. It carries out its own signals intelligence operations and is trying to collect huge amounts of email and Internet data from U.S. companies — an operation that the NSA once conducted, was reprimanded for, and says it abandoned.
The heart of the FBI’s signals intelligence activities is an obscure organization called the Data Intercept Technology Unit, or DITU (pronounced DEE-too). The handful of news articles that mentioned it prior to revelations of NSA surveillance this summer did so mostly in passing. It has barely been discussed in congressional testimony. An NSA PowerPoint presentation given to journalists by former NSA contractor Edward Snowden hints at DITU’s pivotal role in the NSA’s Prism system — it appears as a nondescript box on a flowchart showing how the NSA “task[s]” information to be collected, which is then gathered and delivered by the DITU. [Continue reading…]