Park Dietz

Park Elliot Dietz (born August 13, 1948) is a forensic psychiatrist who has consulted or testified in many high-profile US criminal cases, including those of spousal killer Betty Broderick, mass murderer Jared Lee Loughner, filicide defendant Andrea Yates, and serial killers William Bonin, Jeffrey Dahmer, Ted Kaczynski, Richard Kuklinski, Joel Rifkin, and Arthur Shawcross. He came to national prominence in 1982 during his five days of testimony as the prosecution's expert witness in the trial of John Hinckley Jr., who had attempted the assassination of President Reagan on March 30, 1981. Then an assistant professor of psychiatry at Harvard Medical School, Dietz testified that at the time of the shooting, Hinckley knew that his actions were wrong and had the capacity to control his behavior, and was therefore not legally insane. He now heads a forensic consulting firm, Park Dietz & Associates, and founded the world's first workplace violence prevention company, Threat Assessment Group, Inc.