Former Watergate prosecutor on MSNBC explains why the latest Cohen news should terrify Trump on several fronts

Jill Wine-Banks, a former Watergate prosecutor, told MSNBC's Stephanie Ruhle on Monday that Rudy Giuliani's attacks on Michael Cohen's honesty notwithstanding, the president should be worried that his former fixer could be "very valuable" to the Mueller investigation. Cohen pled guilty in August to breaking campaign finance laws and admitted to paying women "hush money" to keep quiet about their affairs with then-candidate Trump. On Thursday it was revealed he sat for multiple interviews with special counsel Robert Mueller over the past month.

"Even if he's just corroborating the documents that have been seized from his office and his home, that would be important," Wine-Banks said. "A lot of times when you even have tapes of conversations which we know he had, and you have e-mails they aren't as clear as you might think they would be, and they need some testimony to explain what they mean."

"He can be very valuable," she added, ticking off several areas potential trouble for the president. "We know that he was in Russia for the Trump Tower Moscow. We know that he has been involved in paying off women. We know that he knows a lot about the business of Donald Trump in New York."

Wine-Banks acknowledged that Cohen "is not the most trustworthy person." But, she added, "neither is the president, and it depends on where the circumstantial evidence and corroboration comes from. I would trust him if his documents support him."

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