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 Russian Federation investigation.
Alex van der Zwaan, who worked with Gates and former Trump campaign chairman Paul Manafort while he practiced law at a large worldwide firm, admitted to lying and failing to turn over emails to Mueller's team in February.
Van der Zwaan will also have to undergo two months of supervised release after he serves his prison term.
The Dutch son-in-law of one of Russia's richest men has been jailed and fined $US20,000 ($A26,000) for lying to Special Counsel Robert Mueller's investigators about contacts with an official in President Donald Trump's 2016 campaign.
Alex van der Zwaan - a Dutch national who faced up to six months in prison under federal sentencing guidelines - is the first person to have been indicted in connection with the case.
Jackson said she did not know if van der Zwaan was motivated to join Manafort and Gates for excitement, the money, or was engaged in a deeper "coverup", but that in lying "he put his own interests ahead of the interests of justice" in an investigation of national and worldwide importance into whether the USA democratic process was corrupted.
Gates and Manafort were indicted past year on charges related to laundering tens of millions of dollars and failing to register as agents acting on behalf of a foreign government.
"He is literally in limbo", Mr Schwartz said.
Whether he committed any crimes "arising out of payments he received from the Ukrainian government before and during the tenure of President Viktor Yanukovych".
Van der Zwaan had pleaded guilty in February.
A court filing Monday night revealed an August 2 memo that showed the Department of Justice's backing authorized Mueller to go after Manafort for allegedly working with Russian Federation to interfere in the election "in violation of United States law".
"We count on people to tell us the truth", said prosecutor Andrew Weissman.
Van der Zwaan last June married Eva Khan, the daughter of Khan.
Mueller's team questioned van der Zwaan last November during its investigation into Manafort and Gates, according to Newsweek. He had asked the judge for leniency hoping to avoid jail time because his wife is pregnant with their first child.
Prosecutors have alleged that Manafort and Gates used an offshore account to secretly pay $4 million for the report.
The firm, which is co-operating with the investigation and which fired him previous year, worked with former Trump campaign chief Paul Manafort and his ex-colleague Mr Gates at a time when they were both political consultants in Ukraine.