By Tessa Berenson
April 3, 2018

Alex van der Zwaan just became the first person sentenced in Robert Mueller’s investigation.

The Dutch attorney pleaded guilty in February to lying to federal agents, and U.S. District Court Judge Amy Berman Jackson sentenced him on April 3.

Here’s what you need to know about van der Zwaan, one of 19 people charged in the special counsel’s investigation into Russian meddling in the 2016 election so far.

Who is Alex van der Zwaan?

Van der Zwaan is a London-based Dutch attorney who worked for the law firm Skadden, Arps, Slate, Meagher & Flom. The firm fired him last year and is cooperating with the investigation, BBC reports. He is the son-in-law of Ukranian-Russian billionaire German Khan.

How does this tie into Robert Mueller’s Russia investigation?

Van der Zwaan has no known ties to Donald Trump’s presidential campaign, but he worked on Ukranian matters with with Trump campaign chairman Paul Manafort and deputy Rick Gates, both of whom have been charged by Mueller. (Gates has pleaded guilty to lying to investigators and Manafort is awaiting trial.) In sentencing documents, Mueller claims that van der Zwaan and Gates held discussions with a former Russian intelligence officer at the end of the 2016 campaign, ABC reports. Mueller’s team questioned van der Zwaan last November during its investigation into Manafort and Gates, according to Newsweek. In that interview, van der Zwaan lied about when he was last in contact with Gates and someone in Ukraine that prosecutors called “Person A.”

What was he charged with?

Mueller indicted van der Zwaan for making false statements of FBI investigators. According to the indictment, van der Zwaan lied about his interactions with Gates and “Person A,” lied about conversations related to a report his law firm prepared on the trial of a Ukrainian politician, and “deleted and otherwise did not produce emails sought by the special counsel’s office.”

What is his sentence?

Van der Zwaan received a 30-day prison sentence as well as a $20,000 fine and two months probation. Politico reports that his lawyers had asked the judge to let him return home to London by August, when his wife is due to give birth. Judge Jackson said he can leave the country after his 30-day sentence. “We’re not talking about a traffic ticket,” she said. “This was lying to a federal officer in the course of a criminal investigation.”

Write to Tessa Berenson at tessa.berenson@time.com.

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