'Docs don't lie': Ex-insider says Trump lawyers can't rely on trashing Michael Cohen

Former President Donald Trump's lawyers have been telegraphing that they plan to undermine Manhattan District Attorney Alvin Bragg's case against him by attacking the credibility of Michael Cohen, who will be a key witness.

However, one former insider thinks that strategy may be insufficient to get Trump off the hook if prosecutors have done their jobs correctly.

Writing in the New York Times, former assistant Manhattan District attorney Rebecca Roiphe argued that the Manhattan case against Trump is "important and straightforward," and she said that at its heart it's really about business accountability rather than politics.

When it comes to Cohen's testimony, Roiphe acknowledges that he has lots of "baggage" given that he had previously been found guilty of lying under oath on Trump's behalf, but she believes that the DA's office can produce a paper trail that will overcome the former Trump "fixer's" deficiencies.

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"As with most business records cases, his testimony will largely add color to the tweets, handwritten notes, bank documents and shell corporations," she argued. "Documents don’t lie."

With this in mind, Roiphe warned Trump's lawyers that they could be making a major strategic error in trying to paint their client as an innocent "family man."

"In their opening remarks, Mr. Trump’s lawyers insisted that he was innocent, that all the witnesses were liars," she said. "Such a sweeping theory is a dangerous strategy because if the jurors believe part of the prosecution’s case, just one or two of the witnesses, then the jurors may lose faith in the defense altogether."

Roiphe also argued that putting Trump on trial for his alleged offenses is not a political "witch hunt," but simply a normal application of the law.

"It is a simple case that is similar to hundreds of other cases brought in New York," she contended. "The simplicity and run-of-the-mill nature of the prosecution makes it easier to defend against claims of politicization in the following sense: Mr. Trump was a businessman for many years in New York long before he was president. If others would be prosecuted for this conduct and no man is above the law, then he should be, too."