Lev Parnas and his business partner, Igor Fruman, who had climbed to prominent places in the orbit of President Donald J. Trump, were arrested before boarding the flight and charged with several campaign finance violations, including conspiring to funnel a Russian tycoon’s money into American politics.
Prosecutors said records showed that a $325,000 donation to the super PAC backing Mr. Trump, America First Action, Inc. had been falsely reported as coming from Global Energy Producers, a company started by Mr. Parnas and Mr. Fruman. In reality, the prosecutors said, the money came from a loan Mr. Fruman had taken out on a condo he owned.
Mr. Parnas and Mr. Fruman shared pictures of themselves with political figures, including Mr. Trump, Mr. Giuliani and Ron DeSantis, the Republican candidate for governor in Florida at the time.
By the time the trial began, Mr. Parnas had long soured on Mr. Giuliani and Mr. Trump, saying he regretted ever trusting them.
In addition to providing material to the House Intelligence Committee as part of its impeachment inquiry, he made public a phone video from a small dinner in early 2018 at the Trump Hotel in Washington at which Mr. Trump, referring to [ambassador] Yovanovitch, said “get rid of her.”
After the arrest at the airport, Mr. Trump told reporters he did not know Mr. Parnas.