(WASHINGTON) — It’s not only the contents of the Senate’s CIA report that are causing controversy. It’s also the cost.

The five-year review, which examined more than six million CIA documents, came with a price tag of $40 million. That eye-popping figure, costly even by Washington standards, has been seized upon by Republican critics of the report.

But Sen. Dianne Feinstein, chairwoman of the Select Intelligence Committee, says the vast majority of the cost is attributed to the CIA, which insisted on renting a separate building for the review.

“Rather than provide documents for the committee to review in its own secure Senate office, as is standard practice, the CIA insisted on establishing a separate leased facility and a stand-alone computer network for committee use,” Feinstein, D-Calif., said in a statement Wednesday. “The CIA hired teams of contractors to review every document, multiple times, to ensure they were relevant and not potentially subject to a claim of executive privilege. Only after those costly reviews were the documents then provided to committee staff.”

Feinstein said the CIA insisted on hiring outside contractors to review every document, often multiple times. She said she wrote several letters to the CIA over the years, raising questions about the cost.

The unusual arrangement of working in a separate facility, rather than at CIA headquarters or in a secure room on Capitol Hill, led to the allegations that the CIA was spying on Senate computers. Feinstein accused the CIA of obscuring the committee’s investigation and gaining access to Senate computers, which led CIA Director John Brennan to apologize.

Intelligence officials told ABC News on Wednesday that the agency had to work in a separate facility to "ensure the secure exchange" of materials. Six to 12 workers were hired by the CIA to deal with requests related to the Senate inquiry.

“The committee’s demands of CIA in this investigation were unprecedented and the accommodation by CIA was unprecedented,” a CIA spokesman said in a statement. “The agency was forced to devote thousands and thousands of man hours and extensive resources responding to Committee requests related to this investigation over more than a five-year period.”

 
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