Gregory George Katsas

Gregory George Katsas (born August 6, 1964) is a United States circuit judge on the Court of Appeals for the District of Columbia Circuit. Appointed by President Donald J. Trump in 2017, he has served on the nation’s second‑most influential appellate court, handling cases that often involve federal regulatory and administrative law. Prior to his judicial appointment, Katsas held senior positions in both the executive branch and private practice, including Deputy White House Counsel during the first Trump administration, assistant attorney general for the Civil Division of the Department of Justice, and partnership at the Washington, D.C., office of Jones Day. His career has combined extensive appellate litigation experience with service in high‑level governmental legal roles.

Early life and legal career

Gregory Katsas was born on August 6, 1964, in Boston, Massachusetts, to parents who had immigrated from Greece. He pursued undergraduate studies at Princeton University, graduating cum laude in 1986 with a Bachelor of Arts in philosophy. Continuing his education at Harvard Law School, he earned a Juris Doctor cum laude in 1989 while serving as an executive editor of the Harvard Law Review and as an editor of the Harvard Journal of Law & Public Policy.

Following law school, Katsas began his legal career through clerkships that placed him alongside prominent jurists. From 1989 to 1990 he served as a law clerk for Judge Edward R. Becker of the United States Court of Appeals for the Third Circuit. He then clerked for Judge Clarence Thomas of the District of Columbia Circuit from 1990 until Thomas’s elevation to the Supreme Court in 1991, after which Katsas continued as a clerk for Justice Thomas on the nation’s highest court through 1992.

In 1992 Katsas entered private practice at Jones Day’s Washington, D.C., office. Over the next nine years he focused on civil and appellate litigation, arguing more than seventy‑five appeals before various federal courts and presenting three cases before the Supreme Court. His work earned him partnership status in 1999. In 2001 Katsas transitioned to public service within the Department of Justice, where he held several senior positions until 2009. Notably, he served as assistant attorney general for the Civil Division and later as Acting associate attorney general, overseeing significant civil litigation matters on behalf of the United States.

After leaving the Justice Department, Katsas returned to Jones Day in 2009, resuming his practice in appellate advocacy. He remained with the firm until early 2017, when he entered the executive branch as Deputy White House Counsel, a role he held from January through December of that year. In this capacity he provided legal advice to the President and senior administration officials on a range of policy and constitutional issues.

Federal appellate service

President Donald J. Trump nominated Katsas to the United States Court of Appeals for the District of Columbia Circuit on September 7, 2017, filling the vacancy created by Judge Janice Rogers Brown’s retirement on August 31, 2017. The nomination proceeded to a Senate Judiciary Committee hearing held on October 17, 2017. The committee reported his nomination favorably on November 9, 2017, with an 11–9 vote.

The full Senate considered the nomination in late November. On November 27, 2017 the Senate invoked cloture on Katsas’s confirmation by a vote of 52–48, and the following day, November 28, 2017, confirmed him by a 50–48 party‑line vote, with two senators—John Neely Kennedy (R‑LA) and Joe Manchin (D‑WV)—voting opposite to their parties. He received his judicial commission on December 8, 2017, and has served as an active circuit judge since that time.

Since joining the D.C. Circuit, Judge Katsas has become noted for the number of his law clerks who have subsequently clerked for Supreme Court justices. According to reporting by the National Law Journal, he has placed at least eighteen former clerks on the high court beginning with the October 2019 term, making him one of the most prolific “feeder” judges on the appellate bench.

Jurisprudence and legacy

Judge Katsas’s judicial record reflects engagement with a range of complex legal issues. In 2017 he recused himself from matters related to the special counsel investigation led by Robert Mueller, citing his prior involvement in the probe as a basis for stepping aside while indicating that future decisions on recusal would be fact‑based.

His reputation within conservative legal circles was highlighted when President Trump listed him among potential nominees for the Supreme Court on September 9, 2020. He has been mentioned again as a possible candidate for elevation to the nation’s highest court in subsequent discussions.

On July 6, 2021, Judge Katsas cast the decisive vote in a 2–1 panel decision that overturned an FDA ban on electrical stimulation devices used by the Judge Rotenberg Center for individuals with disabilities. His tie‑breaking vote restored the use of those devices pending further regulatory review.

In April 2023, he authored a dissenting opinion in *Fischer v. United States*, a case concerning the application of 18 U.S.C. § 1512(c) of the Sarbanes–Oxley Act to participants in the events of January 6, 2021. In his dissent, Judge Katsas argued that the statutory language and longstanding precedent limited the provision’s reach to conduct affecting the integrity or availability of evidence, and he warned that a broader interpretation would be constitutionally problematic.

Beyond his judicial duties, Judge Katsas maintains involvement in professional organizations. He is a member of the Federalist Society, an association of lawyers and scholars with an interest in textualist and originalist approaches to constitutional interpretation, and he belongs to the American Academy of Appellate Lawyers, which recognizes excellence in appellate practice.

His public service has been recognized through awards as well. In 2009, while serving within the Department of Justice, he received the Edmund Randolph award, the department’s highest honor for outstanding service.

Judge Katsas has also contributed to legal scholarship. His 2015 article, “Targeted Drone Killings: Legal Justifications Under the Bush and Obama Administrations,” appeared in the *Harvard Journal of Law & Public Policy* (volume 38, issue 1) and examined the evolving legal framework surrounding executive‑branch use of unmanned aerial systems for targeted killings.

Through a career that spans private practice, high‑level government service, and federal appellate adjudication, Gregory G. Katsas has played a significant role in shaping contemporary American jurisprudence, particularly within the specialized jurisdiction of the District of Columbia Circuit. His decisions, scholarly work, and mentorship of clerks continue to influence both the development of the law and the pipeline of legal talent advancing to the nation’s highest courts.