Rick Gates, Manafort's former partner in crime (literally, it turns out), took the stand to detail the many shady sides of the worldwide lobbying business he helped the ex-superlobbyist run for years.
Gates, who has been cooperating with Special Counsel Robert Mueller's investigation, is the star prosecution witness in Manafort's fraud trial in Alexandria, Va.
Rick Gates has been regarded as a crucial government witness ever since he pleaded guilty a year ago and agreed to cooperate in special counsel Robert Mueller's investigation.
Asonye followed up by asking, "Did you commit any crimes with Mr. Manafort?"
Ms Laporta detailed multiple examples in which Mr Manafort and Mr Gates sought to doctor financial records, first in order to lower Mr Manafort's taxable income and then later to inflate his income so he could get bank loans.More news: China threatens new tariffs on $60 bn worth of US goods
"I added money to expense reports and created expense reports" that were not accurate, he said, to pad his salary by "several hundred thousand [dollars]".
Similar to prior witnesses, Ms Laporta testified Mr Gates and Mr Manafort were in lockstep but that Mr Manafort was in charge. Later, they say, when that income dwindled, Manafort launched a different scheme, shoring up his struggling finances by using doctored documents to obtain millions more in bank loans.
Gates pleaded guilty in February to a bank fraud conspiracy charge in exchange for testifying against his former boss.
Prosecutors on Monday went through a list of overseas corporations and Gates testified that all of them were controlled by Manafort and contained income earned by his political consulting work.
Manafort's defense hinges on convincing a jury that it was Gates, not Manafort, who committed all of these crimes, and that Manafort is a victim of Gates.
Gates and Manafort have known each other for two decades and ran a multimillion-dollar political consulting business.More news: Donald Trump defends Donald Trump Jr. Trump Tower meeting
Gates also admitted he embezzled money from his boss - something Manafort's attorneys have alleged for months. Mueller is also investigating possible coordination between Trump campaign members and Russian officials in the election campaign, but the charges against Manafort do not address that.
In questioning Laporta on Monday, a prosecutor asked the accountant about a $10 million (£7.72 million) loan purportedly received by Manafort from Russian businessman Oleg Deripaska in 2006.
But Laporta's testimony raised the stakes for Manafort, legal experts said.
Gates testified that he and Manafort had 15 foreign accounts they did not report to the US government, and knew that was illegal.
U.S. District Judge T.S. Ellis III, who repeatedly interrupted prosecutors last week as they tried to present evidence about Manafort's lavish life - including $900,000 in expensive suits and a $15,000 ostrich jacket - clashed again with prosecutor Greg Andres on Monday when Andres delved into the status and identities of the Eastern Europeans who made payments to Manafort.
Under cross-examination, she said at the time she believed Manafort was directing Gates' actions and "knew what was going on".More news: Switzerland crash: Up to 20 feared dead as WW2 plane crash
Gates said he conspired with Manafort to falsify tax returns, knowingly failed to report foreign bank accounts and failed to register Manafort as a foreign agent.