Richard Painter, a former ethics chief in the George W. Bush White House, said the Robert Mueller investigation might come down to just one question: Why did Donald Trump fire James Comey as FBI director?

If it turns out it was to block the Russia investigation, that would be obstruction, Painter said on MSNBC on Wednesday. And that, he predicted, would be the end of this administration.

Earlier Wednesday, The New York Times had reported that special counsel Mueller was seeking information and documents related to the decision to fire Comey in May, among other requests.

“The president once again has the right to fire the FBI director,” Painter said on MSNBC. “But not the right the fire to FBI director in order to obstruct an ongoing investigation of the collaboration with the Russians.”

He added:

“And there’s obviously collaboration. They’ve got to stop denying that. The only question is whether it was illegal collaboration. But the obstruction of justice and the lying ultimately may be what puts an end to this White House. They are in serious trouble on this.”

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