About Karl M.
Karl M. Tilleman is an Arizona-based lawyer whose career has moved between the highest courts and large national firms. He earned a Bachelor of Science in psychology from the University of Calgary in 1986 and a J.D. from Brigham Young University’s J. Reuben Clark Law School in 1990. Those academic years set a pattern: rigorous study followed by work at the appellate level.
After law school, Tilleman clerked for Judge John T. Noonan on the U.S. Court of Appeals for the Ninth Circuit in 1990. That year in chambers came before a two-year stint at the Supreme Court of the United States, where he served as a law clerk to Chief Justice Warren Burger and to Justice Clarence Thomas in 1992. Those clerkships placed him at the heart of appellate practice early in his career and exposed him to federal litigation at its most consequential.
Following his time on the bench, Tilleman entered private practice. He became a partner at Steptoe & Johnson LLP in 2000, joining a firm known for national litigation and appellate work. Over the years he built experience handling complex legal questions and representing clients in federal courts. His path through major firms continued when he joined Dentons US LLP as a partner, bringing the appellate and federal court experience he had developed in earlier roles.
Colleagues describe him as an attorney who moves comfortably between litigation and appellate tasks. He has practical familiarity with brief writing, legal research, and preparation for argument. Those skills reflect the training he received in appellate chambers and the types of matters he has handled at national law firms.
Tilleman maintains membership in the Arizona State Bar and practices under that jurisdiction. He is based at Dentons US LLP’s Arizona office, where he works on matters that require attention to federal and appellate procedure. He remains connected to the institutions that shaped his early career—courts, law clerks, and large firm litigation teams—while practicing in a state-level bar environment.
He is currently a partner at Dentons US LLP in Arizona, where his practice focuses on appellate and federal court matters.
