WATCH: Intel Dem suggests Paul Manafort fears Putin and poison more than prison

Former Donald Trump campaign chair Paul Manafort may fear retribution from Russian Federation President Vladimir Putin more than he fears spending the rest of his life in prison.

Rep. Eric Swalwell (D-CA), a former prosecutor who sits on the Intelligence and Judiciary committees, explained the dynamic during a Tuesday appearance on MSNBC's "Deadline: White House."

Host Nicolle Wallace asked about Manafort, former Trump National Security Advisor Michael Flynn and longtime Trump fixer Michael Cohen all staying in the news as their criminal cases move through the court system.

"Well, first, I would say, come clean and you come out okay," Swalwell advised. "If you continue to lie, deny, tamper, obstruct, and prevent investigators from getting to the truth, you could spend the rest of your life in prison."

"Now, as many have said, I don't think the word that Paul Manafort fears that starts with 'p' and ends with 'n' is 'prison,' I think it's probably 'Putin' or 'poison' -- so who knows whether that is a motivating factor for him," Swalwell noted.

"But I think we now have the clearest picture yet that Donald Trump, his campaign, his family, and his businesses, did all they could to work with the Russians to also do business in Russia and sixteen of them when confronted about it all lied," he added.

Swalwell doubted whether special counsel Robert Mueller was closely examining whether Russia was blackmailing Trump, but vowed House Democrats would "investigate Deutsche bank, look at the president's tax returns, his financial records, to see if his interests over decades to do business with the Russians and the Russians' efforts to do business with him has materialized to a president being compromised."

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