Story highlights McCaskill said, "the facts speak for themselves"

The WH initially cited Rosenstein's memo as the reason to fire Comey

Washington (CNN) Democratic Sen. Claire McCaskill said deputy Attorney General Rod Rosenstein knew President Donald Trump was going to fire FBI Director James Comey before he wrote a memo recommending Trump do that.

Rosenstein gave a classified briefing for the full Senate in private on Thursday afternoon more than a week after Trump fired Comey and a day after he appointed former FBI Director Robert Mueller as special counsel for all things related to Russian attempts to influence the 2016 election.

Because it was a closed briefing, it's unclear exactly how Rosenstein described how he knew Trump would fire Comey. But Sens. Tom Carper and Dick Durbin, both Democrats, and Sen. Susan Collins, a Republican, also confirmed similar details revealed during the briefing.

"(Rosenstein) did acknowledge that he learned Comey would be removed prior to him writing his memo," McCaskill said. "He knew that Comey was going to be removed prior to him writing his memo," she said again.

McCaskill said "the facts speak for themselves" on that matter and declined to comment further, saying she needed more facts, documents and sworn testimony.

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