In testimony before Congress, former top FBI lawyer James Baker confirmed that senior bureau officials discussed the possibility that President Donald Trump fired FBI Director James Comey, “at the behest of” Russia to end the Russian probe last May.

Trump’s on-air proclaimed that he fired Comey because he was a “nut job” after his Oval Office meeting with multiple Russian officials worried Baker. In a discussion Baker had with Andrew McCabe, Carl Ghattas and Bill Priestap, Baker said he thought it was possible that Trump fired Comey “acting at the behest of [Russia] and somehow following directions, somehow executing their will.”

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Though Republicans have questioned  Baker’s statement, they believe that senior FBI officials were biased against Trump, notably McCabe and Peter Strzok. McCabe and Strzok were both fired by the FBI subsequently. Both have denied their personal views of Trump affected the decisions they made at the FBI prior to leaving.

Baker said that the discussion between the senior officials was purely meant to assess the possibilities behind Trump’s decision to fire Comey.

“We need to investigate, because we don’t know whether, you know, the worst-case scenario is possibly true or the president is totally innocent and we need to get this thing over with — and so he can move forward with his agenda,” Baker said.

Baker also spoke about the conversation between McCabe and Deputy Attorney General Rod Rosenstein about Rosenstein possibly wearing a wire to collect evidence in the obstruction probe. Though many close to Rosenstein believed it was a joke, Baker noted that “this was not a joking sort of time. This was pretty dark.”