Gregory George Katsas (born August 6, 1964) is an American lawyer and jurist serving since 2017 as a U.S. circuit judge of the U.S. Court of Appeals for the District of Columbia Circuit.^[1] Before becoming a federal judge, Katsas served as Deputy White House Counsel to President Donald Trump, as an Assistant Attorney General in the U.S. Department of Justice, and as a partner at the law firm Jones Day.

Katsas was born in 1964 in Boston, Massachusetts. His parents were Greek immigrants.^[2] Katsas graduated from Princeton University in 1986 with a Bachelor of Arts, cum laude. He then attended Harvard Law School, where he was an executive editor of the Harvard Law Review and an editor of the Harvard Journal of Law and Public Policy.^[3][4][5] He graduated in 1989 with a Juris Doctor, cum laude.

After law school, Katsas served as a law clerk to Judge Edward R. Becker of the U.S. Court of Appeals for the Third Circuit from 1989 to 1990. From 1990 to 1991, Katsas clerked for Clarence Thomas, who was then a judge of the District of Columbia Circuit. After President George H. W. Bush appointed Thomas to the U.S. Supreme Court in 1991, Katsas again clerked for Thomas from 1991 to 1992.^[6][5]

Katsas then entered private practice at the Washington, D.C., office of the law firm Jones Day, where he specialized in civil and appellate litigation.^[7] He argued more than 75 appeals, including three cases in the U.S. Supreme Court.^[5] He was at Jones Day from 1992 to 2001, becoming a partner in 1999.^[6]

From 2001 to 2009, Katsas served in various positions within the United States Department of Justice, including Assistant Attorney General for the Civil Division and Acting Associate Attorney General.^[5] Katsas returned to Jones Day from 2009 to 2017. From January to December 2017, Katsas served as Deputy White House Counsel.

On September 7, 2017, President Donald Trump nominated Katsas to serve as a United States Circuit Judge of the United States Court of Appeals for the District of Columbia Circuit, to the seat vacated by Judge Janice Rogers Brown, who retired on August 31, 2017.^[8][9]

On October 17, 2017, a hearing on his nomination was held before the Senate Judiciary Committee.^[10] On November 9, 2017, his nomination was reported out of committee by an 11–9 vote.^[11][12]

On November 27, 2017, the United States Senate invoked cloture on his nomination by a 52–48 vote.^[13] On November 28, 2017, by a party line vote except for John Neely Kennedy R-LA^[14] and Joe Manchin D-WV, with Bob Corker and John McCain absent, Katsas was confirmed by a 50–48 vote.^[15] He received his judicial commission on December 8, 2017.^[16]

In 2017, Katsas recused himself from matters regarding the Mueller probe on which he personally worked, but said he would consider the facts of a case before making a decision.^[17]

On September 9, 2020, President Trump included him on a list of his potential nominees to the Supreme Court.^[18]

On July 6, 2021, Judge Katsas gave the tie-breaking 2-1 vote that overturned the FDA's ban on GEDs used predominantly by the Judge Rotenberg Center on disabled patients in Canton, MA.^[19]

He is a member of the Federalist Society,^[20] and also a member of the American Academy of Appellate Lawyers.^[6]

In 2009, he was awarded the Edmund Randolph award for outstanding service, the highest award bestowed by the U.S. Department of Justice.^[6]

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