Park Dietz

Park Dietz (born 1948) is a forensic psychiatrist who was educated at Cornell, Johns Hopkins, and the University of Pennsylvania. As a full-time academic at Harvard Medical School and the University of Virginia Schools of Law and Medicine, he contributed over 100 publications to the professional literature, including seminal work on the epidemiology of violence, sex offenses, and the stalking of public figures. He founded the first company devoted to the prevention of violence in the workplace (Threat Assessment Group, Inc.). He is an honorary member of Sigma Pi.

He has interviewed, and testified at the trials of, Jeffrey Dahmer, John Hinckley, Andrea Yates, and many more murderers of the last 30 years.

Since the mid-1990s, Dietz has served as a consultant for the "Law & Order" TV shows. This association has led to controversy. As a prosecution witness in the Andrea Yates trial, Dr. Dietz became involved in a controversy when he gave false testimony while being cross-examined by the defense. Under questioning by Yates's defense attorney, Dietz stated that shortly before the killings, an episode of Law & Order had aired featuring a woman who drowned her children being acquitted of murder by reason of insanity. Within a week of his testimony, Dietz discovered that no such episode of Law & Order existed. Dietz notified the prosecution of his mistake and submitted a letter to the Judge stipulating to his mistake. In fact, Dietz's mistake was that he had confused a similar episode of "L.A. Law" which had re-run in the same time period. Nevertheless, in their closing statement, the prosecution reminded the jury that witnesses had stated that Andrea Yates regularly watched re-runs of Law & Order and that there had been an episode of Law & Order paralleling the events of Yates' crime. On January 6, 2005, the Texas Court of Appeals reversed the convictions of Andrea Yates because the appellate court held that the jury may have been influenced by Dietz's mistaken testimony and that thus a new trial would be necessary. On January 25, 2005, Dietz again provided false testimony during a Daubert hearing in the U.S. District Court of Western Tennessee, Judge Donald presiding. In an instance where he had never interviewed the defendant, Dietz testified the defendant had been influenced by a "recent high profile case" that had been widely reported in the media. Under cross examination Dietz identified the case as that of the Eire PA, pizza delivery driver who was killed by a neck bomb 14 months after the incident involving the defendant. Court transcripts indicate Dietz's only reaction to this revelation by defense counsel was "Wow." The defendant was subsequently exonerated of all charges.

In a documentary called Conversations With Killers, Dietz recalls his encounters with criminals.

Park Dietz also contributed to the Attorney General's Commission on Pornography as a commissioner recommended by the White House and appointed by the Attorney General of the United States. His personal statement in the Commission's report was widely circulated for years, and the report appendixed a study Dietz had published on detective magazines with bondage covers.