Samuel Anderson Thumma

Samuel A. Thumma has served as a judge on the Arizona Court of Appeals, Division One, in Phoenix since 2012, serving as Chief Judge (2017-19) and Vice Chief Judge (2015-17). Before that, he served for five years as a trial judge (criminal and juvenile rotations) on the Arizona Superior Court in Maricopa County, presiding over nearly 250 trials and serving as an elected member of the Judicial Executive Committee.

Nationally, Sam is a member of the National Judicial College Board of Trustees (2024-present), where he serves as Board secretary. Sam has been a Uniform Law Commissioner from Arizona since 2012, most recently completing a two-year term as Secretary of the Executive Committee. Currently, Sam serves as chair of the ULC Joint Editorial Board on Civil Litigation and Dispute Resolution and chair of the Study Committee on the Protection of Name, Image and Likeness. A member of the American Law Institute since 2003, Sam is an Advisor to the ALI’s Restatement of the Law (Third) of Torts:  Remedies. Since 2018, Sam has served as a member of the Joint Technology Committee, appointed by the National Center for State Courts. He is a member of the Editorial Board for Judicature.

In the American Bar Association, Sam serves as a Presidential appointee to the Advisory Council of the ABA Task Force on Law and Artificial Intelligence, having previously served on the Standing Committees on Lawyer Referral and Information Services and on Ethics and Professional Responsibility Judges Advisory Committee. In the ABA Judicial Division, Sam is a member of the Ethics and Professionalism Committee and the Court Technology Committee. He is a past chair of the ABA JD Appellate Judges Conference, and is a past chair of the Appellate Judges Education Institute, Inc., Board of Directors. He served as chair of the Education Committee for the 2019 AJEI Summit, held in Washington, D.C.

In Arizona, Sam has chaired various Committees, Commissions and Task Forces for the Arizona Supreme Court and the State Bar of Arizona. Currently, he chairs the Arizona Commission on Access to Justice; co-chaired the Advisory Committee on Evidence Retention and the COVID-19 Continuity of Court Operations During Public Health Emergency Workgroup (the Plan B Workgroup) and was co-editor of the Arizona Appellate Handbook for many years. He also chaired the Judicial Ethics Advisory Committee, the Task Force on Court Management of Digital Evidence and the Task Force to Supplement Keeping of the Record by Electronic Means. For nine years, Sam served as a member of the State Bar of Arizona’s Committee on the Rules of Professional Conduct (the Ethics Committee).

In 2025, Sam received the Chief Justice Richard W. Holmes Award of Merit, awarded by the American Judges Association for outstanding contributions to the judiciary. In 2023, Sam received the James A. Walsh Outstanding Jurist Award from the State Bar of Arizona, and, in 2021, he was named the Judge of the Year by the Arizona Supreme Court. Sam has co-taught evidence at the Arizona State University Sandra Day O’Connor College of Law for four years, having previously co-taught evidence to all new Arizona trial judges for many years. He has taught remedies at the University of Arizona and Arizona State University Colleges of Law and has taught nearly 600 law-related seminars, in person and remote, internationally, nationally, and locally. Sam is a frequent author, having published 22 law review articles, seven book chapters and nearly 80 other law-related articles, with his work frequently cited by others.

Before joining the bench, Sam was an AV peer review rated lawyer and a partner at Perkins Coie Brown & Bain, P.A., in Phoenix, and an associate at Arnold & Porter in Washington, D.C. He served as a law clerk for Arizona Supreme Court Chief Justice Stanley G. Feldman and Judge David R. Hansen, United States District Court for the Northern District of Iowa. Sam received a Master of Laws from Duke University School of Law in 2020; graduated Order of the Coif from the University of Iowa College of Law in 1988, where he was a Note & Comment Editor on the Iowa Law Review, and graduated from Iowa State University in 1984, where he was a Harry S. Truman Memorial Scholar.