Rick Gatesthe key witness in Paul Manaforts trial, testified that he helped President Donald Trumps former campaign chairman commit bank and tax fraud crimes over the past decade.

Manafort and Gates — a former Trump aide — were charged earlier this year for crimes committed while working together for pro-Russia political entities in Ukraine. The charges Manafort received are unrelated to his work as Trump’s campaign manager in 2016. Manafort and his business associate Konstantin Kilimnik were also hit with obstruction of justice charges earlier this year. Prosecutors believe Kilimnik is linked to Russian intelligence agencies.

“I was the one who helped organize the paperwork,” Gates said of the financial crimes he and Manafort committed.

Manafort evaded hundreds of thousands of dollars in taxes by intentionally misreporting his income from his Ukraine work, and recent reports detailed his lavish spending habits. The 69-year-old reportedly spent more than $900,000 on suits and around $15,000 on an ostrich jacket that garnered much attention last week, when Manafort’s trial in Alexandria, Virginia, first began.

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Gates, 46, was also charged with counts unrelated to Manafort, including money laundering and lying to federal investigators. According to the New York Times, Gates “seemingly knew every detail of Mr. Manafort’s finances,” including how much the latter spent on season tickets for his favorite sports team’s games.

Gates said in his testimony that Manafort ordered him to lie to accountants about the former Trump campaign chairman’s control of offshore bank accounts in Cyprus “in the names of shell companies,” per the Times. Gates also told prosecutors that four Ukrainian oligarchs he and Manafort worked for helped to elect a pro-Russian candidate in 2010, and added that the oligarchs paid Manafort millions for this work.

Although these charges are unrelated to special counsel Robert Muellers investigation into Russian interference in the 2016 election, Gates is indirectly connected to this probe because earlier this year, Mueller sentenced Dutch lawyer Alexander van der Zwaan to 30 days in prison for making false statements to the FBI and other federal authorities. Van der Zwaan also reportedly lied about his contacts with Gates.

In February, Gates pleaded guilty to lying to federal investigators and conspiracy to commit fraud. However, he has not yet been sentenced.