April 3 (UPI) -- A federal judge in Washington, D.C., sentenced Dutch lawyer Alex van der Zwaan to 30 days in prison Tuesday for lying to investigators, the first punishment to be meted out in Robert Mueller's Russia investigation.
U.S. District Judge Amy Berman Jackson also ordered van der Zwaan to pay a $20,000 fine and serve two months of supervised release. She told him his lies to federal investigators were not just a mistake and he should have known better because be is a lawyer.
Van der Zwaan, the 33-year-old son-in-law of a Russian oligarch, pleaded guilty in February to lying to investigators about his work in Ukraine with former Trump campaign officials Paul Manafort and Rick Gates.
Van der Zwaan asked to receive no sentence because his wife is six months pregnant.
"What I did was wrong. I apologize to the court, my wife and my family," he told the judge.
Manafort has pleaded not guilty to multiple charges across two indictments stemming from the Mueller probe -- one in February and another in October. He faces tax and fraud charges in the second indictment, and conspiracy and money laundering in the first.
Gates also was named in the two indictments, the latter of which accused the man of lying to banks about their business income in order to get more than $20 million in loans.
A federal judge placed them both under house arrest in October. Manafort is awaiting trial and Gates, who pleaded guilty to reduced charges, is cooperating with Mueller.
Van der Zwaan has no known ties to the Trump campaign but court documents say he and Gates held discussions with a business associate and former Russian intelligence officer during the final months of the 2016 campaign.
Trump has denied "collusion" between his campaign and the Kremlin and has repeatedly called the investigation a "witch hunt." John Dowd, Trump's former attorney, called for Mueller's probe to be shut down.
A court filing Monday night revealed an Aug. 2 memo that showed the Department of Justice's backing authorized Mueller to go after Manafort for allegedly working with Russia to interfere in the election "in violation of United States law."
Mueller was also authorized by Deputy Attorney General Rod Rosenstein to investigate "crimes arising out of payments [Manafort] received from the Ukrainian government before and during the tenure of President Viktor Yanukovych."
The Mueller investigation has so far resulted in criminal charges filed against 19 people -- 13 are Russian nationals who allegedly waged "information warfare" against the United States during the election.
Guilty pleas have been entered from several former Trump campaign and administration officials, including former national security adviser Michael Flynn and campaign foreign policy adviser George Papadopoulos.