Mark Costanzo received his Ph.D. in social psychology from the University of California at Santa Cruz. He is a professor of psychology at Claremont McKenna College and a member of the plenary faculty at Claremont Graduate University. He has published research on a variety of law-related topics including police interrogations, false confessions, jury decision-making, sexual harassment, attorney argumentation, alternative dispute resolution, and the death penalty. He has also published research in the areas of nonverbal communication, teaching techniques, and energy conservation. Professor Costanzo is author of the books, Just Revenge: Costs and Consequences of the Death Penalty and Psychology Applied to Law. He has co-edited four books, including, Expert Psychological Testimony for the Courts and Violence and the Law.
Professor Costanzo has served as a consultant or expert witness for more than 80 criminal cases. In 2008, he was the winner of the Outstanding Teaching and Mentoring Award from the Society for the Psychological Study of Social Issues (SPSSI), and in 2010, he received the Outstanding Teaching and Mentoring Award from the American Psychology-Law Society (APLS).