Former F.B.I. Director James Comey — who was fired by President Donald Trump in May — testified Thursday before the Senate Intelligence Committee. Comey's hearing was peppered with questions about whether Trump tried to lean on Comey to stop investigations into connections between Trump’s associates and Russia. Thursday afternoon, Marc Kasowitz stepped in to defend the president live on television.

Kasowitz is Trump’s personal lawyer. According to a Monday report from the New York Times, Kasowitz is a bit of an outsider and not well-known in Washington. Kasowitz has been Trump’s counsel for a long time and represented Trump in a case prohibiting businessman Carl Icahn from taking over Trump’s three Atlantic City casinos after they went bankrupt. Kasowitz, 64, has also defended Trump in sexual harassment cases and has helped Trump navigate divorce. Kasowitz even sent a letter to the New York Times on behalf of Trump threatening to sue the newspaper for libel during the 2016 presidential election.

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The New York Times says that Kasowitz has a reputation as a tough guy and a fighter. His signature bristle came in his Thursday statements, which defended Trump against Comey's allegation that the president was being investigated and had asked for loyalty from the former FBI director.

“Mr. Comey has now finally confirmed publically what he repeatedly told the president privately: the president was not under investigation as part of any probe into Russian interference,” said Kasowitz. “ The president also never told Mr. Comey, ‘I need loyalty, I expect loyalty in form or substance.’”

Kasowitz also went after Comey for what has become a familiar complaint of Trump: leaking.

“Today, Mr. Comey admitted that he unilaterally and surreptitiously made unauthorized disclosures to the press of privileged communications with the president,” Kasowitz said. “The leaks of this privileged information no later than March 2017 when friends of Mr. Comey have stated he disclosed to them the conversations he had with the president … today Mr. Comey admitted that he leaked.”

Kasowitz went on to insinuate that Comey lied during his testimony about the timing of releasing his memos.

Kasowitz has also worked for several other high-profile clients. He is currently representing Bill O’Reilly, the beleaguered former Fox News commentator, in a case involving his firing from the news channel over sexual harassment accusations.

Kasowitz has also represented the owner of the Liggett Group, one of the largest tobacco companies in the United States. He represented Liggett against a class-action lawsuit about negative health effects of tobacco. He navigated a settlement for the company that became a model for other tobacco companies, according to the New York Times.

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Kasowitz represented the Port Authority of New York and New Jersey in a civil case after the 1993 bombing of the World Trade Center, according to the Los Angles Times. And Kasowitz has taken on a new client recently: Russia’s largest bank, Sberbank, who is facing a lawsuit in U.S. District Court.

Kasowitz, like Trump, does not shy away from the limelight. On the website of his law firm, his biography begins with a list of news stories he’s been featured in.