Mueller's star witness Rick Gates is about to take the stand in the trial of Paul Manafort

ALEXANDRIA, Virginia — Paul Manafort’s former deputy and Trump campaign adviser Rick Gates is expected to take the stand Monday afternoon in what will be the most anticipated moment yet in the tax-and-bank fraud trial of President Trump’s former campaign chief.

Manafort's lawyer Kevin Downing said in open court that Mueller's star witness would be called next on the fifth day of the trial. “Mr. Gates is next up," Downing said during a cross-examination of Manafort's accountant Monday.

Manafort’s lawyers have signaled their defense rests largely on showing their client never intended to break the law — and that his primary failing was putting too much trust in Gates. To that end, Manafort’s lawyers have skewered Gates as an untrustworthy deputy engaged in his own nefarious dealings with the company’s accounts, while Manafort’s back was turned.

Manafort’s defense attorney Thomas Zehnle, claimed in the opening statement last Tuesday that Gates “embezzled millions” from their consulting work together, and that Gates “had his hand in the cookie jar.” But Manafort’s team has yet to provide any proof for that assertion, or even give a detailed explanation of what it might mean.

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And they haven’t so far even attempted to answer the question of why Gates would have set out to orchestrate a massive and legally-risky web of offshore accounts, mostly for the benefit of Manafort, without even telling Manafort about what he was up to.

Prosecutors in the case have pushed back, during witness testimony, against the argument that Manafort was simply out to lunch by asking about the attention to financial detail.

“He was very detail-oriented,” said Manafort’s bookkeeper, Heather Washkuhn. “He approved every penny of everything we paid.”

Witnesses have indeed testified, however, that Gates acted as a go-between for Manafort and his financial professionals on numerous occasions.

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But the case against Manafort is also built on an extensive paper trail, and a list of 35 potential witnesses including people who worked closely with Gates and Manafort in Ukraine, their accountants, and others.

Now, if Manafort’s lawyers intend to put all the blame for financial impropriety on Gates, his appearance on the witness stand will be their opportunity to drive that argument home. Failing to do so could mean a guilty verdict that sends Manafort to prison for the rest of his life. Success, even if that only means raising sufficient doubt in jury’s minds about whom to believe, could mean an unlikely victory in a case many analysts have said doesn’t so far seem to be going Manafort’s way.

Cover image: Rick Gates, former campaign aide to U.S. President Donald Trump, departs after a bond hearing at U.S. District Court in Washington, U.S., December 11, 2017. REUTERS/Joshua Roberts/File Photo