WATCH: Paul Manafort may not be cooperating over ‘fears of retaliation’ by the Russians

Former Donald Trump campaign chairman Paul Manafort may have intentionally violated his plea agreement -- effectively giving himself a life sentence behind bars -- in order to avoid retaliation from Russian Federation President Vladimir Putin, MSNBC's "The Last Word" with Lawrence O'Donnell explained on Monday.

"Given his involvement with Russians and people close to Vladimir Putin, and the work he did in Ukraine, when you see what Vladimir Putin is apparently willing to do to people around the world -- including poisonings in London and elsewhere -- is it possible that Paul Manafort is thinking [that] the biggest fear he has is what Putin might decide to do if Paul Manafort becomes a cooperating witness who then eventually is free?" O'Donnell asked.

"It's definitely possible, which sounds a little bit, you know, contradictory," answered Mimi Rocah, a former assistant United States Attorney in the Southern District of New York.

"We don't have sort of evidence with it with respect to Manafort, but we have evidence of Putin's actions with respect to other people who could incriminate him and his actions around the world," she noted. "And that is what we at least think, you know, Manafort could possibly provide."

"And so when you put those things together, it would make sense that's something he is afraid of," she concluded.

"And that goes to Ron's point about if Trump then pardoned him knowing that ... knowing what Manafort could provide, knowing that he's not cooperating, you know, because of fears of retaliation by the Russians -- it's just a really dirty, bad, ugly situation," Rocah explained.

"You can call it a constitutional crisis, but it's just -- it stinks on so many levels, you know, beyond the Constitution," she said.

"It's just something we don't want in this country. We want to find out the truth, and that feels like that is what is being prevented," she added.

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