Andrew R. Klein, Ph.D., retired in 2026 after twenty years at Advocates for Human Potential, Inc, where he directed multiple research projects for the National Institute of Justice and headed the U.S. Justice Department’s technical assistance program for the nation’s prison and jail substance use disorder treatment programs. He is the author of multiple books on criminal justice, domestic violence, and jail deaths, two of which he co-authored with his daughter, Jessica Klein. Previously, he served as chief probation officer in an adult and juvenile Massachusetts court for 25 years. He obtained his BA from Harvard College and Ph.D. in Law, Policy and Society from Northeastern University.