Key witness Michael Cohen to take the stand against Donald Trump

Michael Cohen is finally set to testify in People v. Donald Trump. At this point in the historic New York state criminal trial, with the prosecution already having put on several witnesses and reams of evidence, you might wonder what the state needs from him. And of course there’s the baggage this witness brings and the challenge it poses for each side.

Let’s preview both of those issues ahead of Cohen’s testimony, which is set for Monday in the first-ever criminal trial of a former U.S. president. Manhattan prosecutors told Judge Juan Merchan on Friday that they may rest their case this week.

First, on what prosecutors are looking for from Cohen. The short answer is: direct evidence of Trump’s guilt. Intent is key to proving the charges of falsifying business records, so prosecutors want to bring out as much credible, direct evidence as possible from the ex-fixer.

And how might Cohen do that, exactly?

We can look to the prosecution’s opening statement as a guide. Prosecutor Matthew Colangelo told the jury, referring to hush money recipient Stormy Daniels, that “at Trump’s direction, Cohen negotiated a deal to buy Ms. Daniels’ story in order to prevent American voters from learning that information before Election Day.” Cohen can detail the “at Trump’s direction” part. While his testimony probably won’t surprise the jury — a bunch of evidence against Trump has already been presented — Cohen is in a unique position to offer direct evidence of both the alleged hush money scheme and the reimbursement cover-up that form the basis of the charges.

It’s that unique position that leads to the second point: the baggage. Sure, Cohen has it. The prosecution has been upfront with the jury about that from the start. But it’s important to understand what that baggage is and how harping on it can hurt Trump if his lawyers aren’t careful (indeed, the defense may have miscalculated in how aggressively it cross-examined Daniels).

For one thing, Cohen’s unscrupulous character won’t be a revelation to the jury. His name has come up through other witnesses and not in a good way. Take former Trump aide Hope Hicks, who said that Trump told her, after the Daniels story emerged, that Cohen had paid to silence the adult film star out of the kindness of his heart. Hicks told the jury that that sounded out of character for Cohen, whom she didn’t know to be “charitable” or “selfless.”

Now, no one wants anyone to say that about them. But in the context of this case, that sort of testimony is worse for Trump (the one on trial, after all) than it is for Cohen. It makes the prosecution’s election subversion cover-up theory more likely and the proposition that Cohen went rogue (but was then still reimbursed with fudged records?) sound even less likely.

So before taking the stand, Cohen has already been broadly corroborated by multiple witnesses, even if he’s been personally denigrated in the process. That corroboration is the key point that the state will return to in summation, combining Cohen’s direct evidence against Trump with the mountain of other evidence from other witnesses and the falsified records themselves to argue that there’s no reasonable doubt about the defendant’s guilt. (The former president has pleaded not guilty and has denied the sexual encounter with Daniels.)

Still, this doesn’t mean that Cohen’s testimony will be easy for the prosecution. It’s an open question whether he’ll keep his temper and how any loss of control could play with the jury.

And not every negative thing about Cohen is bad for Trump. But enough of the negative things about Cohen are also bad for Trump that the defense has to be careful on cross. The witness has a criminal history, but at least some of it is Trump-related, including Cohen’s campaign finance–related convictions for conduct that’s at the heart of the alleged scheme in this very trial. Colangelo told the jury in his opening statement that Cohen will testify “that he ultimately pled guilty and went to jail for causing an unlawful corporate contribution in connection with the Karen McDougal payments and for making an excessive campaign contribution in connection with the Stormy Daniels payoff.”

As for that, we won’t have to wait for the defense to bring up Cohen’s dirty deeds. Prosecutors are likely to bring them up first on direct examination, so that it doesn’t seem like they’re hiding anything when the defense goes after him. And while this practice of drawing the sting is typical, in this case it may prompt defense objections to some of the prosecution’s grilling of its own witness, for fear that Trump could get burned, too.

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This article was originally published on MSNBC.com