Written by Luke Cohen and Chris Prentice

NEW YORK (Reuters) – When he took over as Manhattan’s top federal attorney general in late 2021, Damian Williams pledged to prioritize “rooting out corruption in our financial markets.”

Now, with fraud charges filed earlier this week against Sam Bankman-Fried, founder of the bankrupt FTX exchange, Williams has cemented his office’s growing role in prosecuting cryptocurrency-related financial crimes, according to interviews with six former prosecutors.

“Every American attorney is defined in the public eye by some of the biggest cases they bring,” said Harry Sandeck, partner at law firm Patterson Belknap and a former Manhattan federal prosecutor. “This will forever be associated with the current US Attorney General.”

The indictment against Bankman-Fried — who was charged with using billions in stolen client money to buy real estate, pay debts to his hedge fund, Alameda Research, and donate to political campaigns — positions Williams as a primary adversary to a high-profile businessman whose downfall captured public attention and led to calls For further regulation of cryptocurrency platforms.

Bankman-Fried, 30, acknowledged the failure of risk management at FTX but said he did not believe he had criminal liability. His lawyer said he was evaluating his legal options. On Tuesday, a judge in the Bahamas ordered him held there while he contested a US extradition request.

Williams led the Securities and Commodities Task Force for the Southern District of New York (SDNY) before President Joe Biden nominated him to be the district’s top attorney general. Williams, the first black American attorney in the United States, earned his law degree from Yale University and clerked for former Supreme Court Justice John Paul Stevens as well as current Attorney General Merrick Garland when Garland was an appellate judge.

Earlier this year, Williams filed its first insider trading case involving digital assets with charges against a former employee of non-fungible token trading platform OpenSea as well as a former product manager at Coinbase (NASDAQ::Global Inc), an FTX competitor.

Both defendants have pleaded not guilty.

SDNY has long been known as one of the most powerful executors of financial crimes, and some former prosecutors have compared Williams’ series of cryptocurrency-related trials to a focus on insider trading by Preet Bharara, who served as US Attorney from 2009 to 2017 and secured. Convictions of fund managers like Raj Rajaratnam.

Williams was a prosecutor in several high-profile financial crime cases during Bharara’s tenure, including the insider trading conviction of former Goldman Sachs (NYSE:) board member Rajat Gupta and the fraud conviction of a former portfolio manager at Visium Asset Management LP.

“Crypto is the Wild West, but at the end of the day fraud is fraud,” said Mike Ferrara, a former attorney general and now attorney at Kaplan Hecker & Fink LLP in New York. “Damien does a good job of saying, ‘We’re going to push the envelope in cryptocurrency,’ the way Brett has been aggressive about insider trading.”

A spokesman for Williams’ office declined to comment.

“Come visit us before we come to see you.”

Pursuing cryptocurrency prosecutions is not without challenges. Defense attorneys might argue that because the sector is relatively new and questions about how to regulate it are still brewing, their clients have not been clear about how laws designed for traditional finance will apply to them.

“The government is having a hard time keeping up and explaining to industry participants what they are supposed to do,” said Elise Maisel, a professor at New York University School of Law and a former white-collar defense attorney. “With these criminal cases, a lot of the time is organized through enforcement.”

In one setback for prosecutors, three former founders and first employee of cryptocurrency exchange Bitmex — who pleaded guilty to charges brought by Williams’ predecessor of failing to set up an anti-money laundering program — earlier this year received lighter sentences than prosecutors had requested.

The judge in that case said that despite the seriousness of the crime, prosecutors had not brought greater charges of money laundering or fraud, and there were no identifiable victims.

Williams’ office has certainly pursued more traditional financial crime cases, too, with charges filed this year against the founder of Archegos Capital Management for lying to banks to obtain loans before the company collapsed, and against the former chief investment officer of a. unit of German Allianz (ETR: SE) to inflate money results.

Both pleaded not guilty.

In the aftermath of Bankman-Fried’s arrest, Williams has made it clear that he will continue to enforce cryptocurrency laws. On Wednesday, he announced wire fraud conspiracy charges against the founders of two separate cryptocurrency mining and trading companies he dubbed Ponzi schemes.

The five defendants in one case have pleaded not guilty, while the three defendants in the other case have not yet presented their defenses.

Williams told reporters on Tuesday that more charges in the FTX investigation may be possible.

“This investigation is very ongoing and moving very quickly,” Williams said. “To anyone who has engaged in wrongdoing at FTX or Alameda Research and has not yet come forward, I strongly encourage you to come see us before we come to see you.”