WATCH: Lanny Davis reveals he's no longer Michael Cohen's attorney to MSNBC's Rachel Maddow

In an interview with MSNBC's Rachel Maddow, attorney Lanny Davis revealed why he stopped working for Michael Cohen -- the same day the Trump "fixer" was sentenced to three years in prison.

"Lawyers have constraints, and the cases over the sentencing process is completed," Davis told Maddow. "Now my media ability to talk and explain and I can speak much more freely, and I'm now exercising my First Amendment rights."

Davis noted that if Cohen begins cooperating, he could become something of a John Dean figure in the Trump White House

"I am thinking of John Dean in 1974, whose crimes included very serious obstruction of justice, tampering with witnesses, doing a lot of the evil work in the Nixon White House that he ultimately owned up to," the attorney said. "But there was a moment, and he and I have talked about that moment, where he needed to tell the truth about what he had seen and heard, even though he was involving himself in all of those crimes."

"That moment," Davis added, "will come for Michael Cohen."

Watch below: