(CBS News) — Don McGahn’s last day as White House counsel was Wednesday, a senior White House official confirmed to CBS News. McGahn had overseen the judicial selection process for Brett Kavanaugh as well as dozens of federal judges.

President Trump had tweeted in August that McGahn would leave after Kavanaugh had been confirmed.

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Mr. Trump appointed McGahn to the position in November 2016, calling McGahn a “brilliant legal mind” with “excellent character and a deep understanding of constitutional law.” Before entering the White House, McGahn served as general counsel to the Trump campaign and was a partner at Jones Day in Washington, D.C. specializing in political law. He’s also a former FEC chairman and has served as general counsel for the National Republican Congressional Committee (NRCC).

McGahn most recently made headlines after a New York Times report revealed that the lawyer has been cooperating extensively with special counsel Robert Mueller’s probe in the 2016 presidential election, namely if Mr. Trump had obstructed justice during the campaign.

The White House lawyer reportedly took part in three interviews with investigators, totaling some 30 hours of testimony. Mr. Trump, in response to the Times’ reporting, lashed out at the outlet, claiming he “allowed” McGahn and other White House staffers to testify before Mueller’s team of investigators, adding that he has “nothing to hide” in the matter.

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While Mr. Trump’s personal attorney Rudy Giuliani has regularly gone to bat for the president on cable news outlets, Emmett Flood, an attorney for President Clinton in the impeachment proceedings in the 1990s, is rumored to be the likely pick to replace McGahn.

McGahn previously threatened to resign from his position in June of last year,with sources telling CBS News chief White House correspondent Major Garrett at the time that the threat was communicated to senior staff, and was not a direct response to Mr. Trump’s talk of firing Mueller.

McGahn and other White House attorneys have previously have tried to back Mr. Trump off the idea of firing Mueller before he ends his probe, citing numerous risks and a lack of legal basis for his ouster.

— Caroline Linton; Fin Gomez, Katiana Krawchenko, Weijia Jiang and Alan He contributed to this report.

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