Gregory G. Katsas
Official portrait, 2008
Judge of the United States Court of Appeals for the District of Columbia Circuit
Incumbent
Assumed office December 8, 2017
Appointed by	Donald Trump
Preceded by	Janice Rogers Brown
Deputy White House Counsel
In office January 20, 2017 – December 8, 2017
President	Donald Trump
Leader	Don McGahn
United States Assistant Attorney General for the Civil Division
In office July 2008 – January 20, 2009
President	George W. Bush
Preceded by	Peter Keisler
Succeeded by	Tony West
Acting United States Associate Attorney General
In office June 22, 2007 – April 2008
President	George W. Bush
Preceded by	William W. Mercer (acting)
Succeeded by	Kevin J. O'Connor
Personal details
Born	(1964-08-06) August 6, 1964 (age 59) Boston, Massachusetts, U.S.
Political party	Republican
Spouse	Simone Mele
Education	Princeton University ( BA) Harvard University ( JD)

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]

He is currently considered the top “ feeder” judge, sending the highest number of his law clerks to clerk on the Supreme Court since his appointment to the bench in 2018. Katsas “has sent at least 18 of his law clerks to the high court since the October 2019 term,” according to National Law Journal. ^{[17] [18]} Legal commentator David Lat has stated Katsas “feeds so much that he also exhibits breadth, placing clerks with Chief Justice Roberts and Justices Alito, Kavanaugh, and Barrett.” ^[19]

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. ^[20]

On September 9, 2020, President Trump included him on a list of his potential nominees to the Supreme Court. ^[21] He has been suggested as a potential nominee in a second Trump administration. ^[22]

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. ^[23]

On April 7, 2023, Katsas authored a dissent in United States v. Fisher, a case interpreting whether January 6 participants could be charged under 18 U.S.C. § 1512(c), a provision of the Sarbanes–Oxley Act enacted to combat corporate fraud that penalizes anyone who “otherwise obstructs, influences, or impedes any official proceeding.” ^[24] Rejecting the government’s argument, Katsas argued that interpreting “the structure and history of section 1512, and with decades of precedent applying section 1512(c) only to acts that affect the integrity or availability of evidence” suggest that the government’s reading is “implausibly broad and unconstitutional in a significant number of its applications.” ^[25] On appeal, the approach of his dissent was adopted by the Supreme Court in an opinion by Chief Justice John Roberts. ^[26]

He is a member of the Federalist Society, ^[27] 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]

• List of law clerks of the Supreme Court of the United States (Seat 10)
• Donald Trump Supreme Court candidates

• Gregory G. Katsas at the Biographical Directory of Federal Judges, a publication of the Federal Judicial Center.
• Biography at U.S. Court of Appeals for the District of Columbia Circuit
• Gregory G. Katsas at Ballotpedia
• Appearances at the U.S. Supreme Court from the Oyez Project
• Appearances on C-SPAN
• Articles about Greg Katsas. AbovetheLaw.com.