Dr. Demento

Illustration by Bob AulIn March 2002, world-renownedNewport Beach forensic psychiatrist Park Dietz took the witness chair in the final phase of the murder trial of Texas housewife Andrea Yates. Dietz, who is also a technical adviser to the TV show Law N Order, told the jury that Yates, who had drowned her five children in a bathtub, wasn't crazy.

In fact, Dietz claimed, Yates was simply claiming insanity after watching an episode of Law N Order in which a depressed mother drowns her kids in a bathtub but—in a typically gripping finale—is found not guilty by reason of insanity. A few days later, brushing aside the insanity plea, the jury convicted Yates of murder.

The only problem: that particular Law N Order episode never actually aired. Which is another way of saying Yates couldn't have seen the show nor could it have motivated her to kill her kids and get away with it by claiming to be nuts.

Oops.

Now, two years after her conviction, Yates' lawyers are appealing the verdict, citing Dietz's fictional testimony as the main reason for her conviction.

“This was an absolute figment of Dr. Dietz's imagination,” George Parnham, Yates' attorney, recently told the Houston Chronicle. “How he transposed this unbelievable fantasy into fact on the stand is beyond me. I don't think he lied intentionally. But his testimony was so dramatic.”

That dramatic testimony capped one of the most dramatic infant homicide cases in recent memory. In July 2001, shortly after the birth of her fifth child, Yates snapped. Experts would later say the stay-at-home housewife suffered from severe postpartum depression, or that she merely crumbled under the pressure of a loveless marriage to a religious conservative, or was battling demonic schizophrenia; after her arrest, Yates herself told police Satan ordered her to kill the children.

Defense attorneys argued Yates was innocent by reason of insanity—and her depression, augmented by schizophrenic hallucinations, made it impossible for her to know right from wrong.

It wasn't until a few days after the jury rendered its verdict that Dietz sent a letter to the court saying he had made a mistake.

“My memory about the content of the show was incorrect,” Dietz stated. “I was confounding the facts of three filicide cases I worked on—Susan Smith, Amy Grossberg and Melissa Drexler—and two episodes of Law N Order based in part on those cases.”

His letter suggests he's the hardest-working shrink in show business. Although Dietz has occasionally testified for the defense, he's almost exclusively worked with prosecutors. During the past 20 years, he's been involved in some of the highest of high-profile cases involving murder and maniacs—from would-be Reagan assassin John Hinkley and serial killer/cannibal Jeffrey Dahmer to Unabomber Ted Kaczinski, Erik and Lyle Menendez, O.J. Simpson and D.C. sniper John Allen Muhammed.

Dietz is almost as high profile as the whackos he talks about. Besides being a consultant to Law N Order, Dietz appeared in the HBO documentary Ice Man, about a real-life Tony Soprano who raised a family in New Jersey while carrying out dozens of gruesome Mafia hits. More recently, in a Dec. 21 broadcast of CNN's Anderson Cooper 360 Degrees, Dietz discussed the phenomenon of women who fake pregnancy, then murder pregnant women to claim the fetuses as their own: they're not crazy, Dietz said, just plain mean. “It takes both normality in the desire to have a child and also a complete sense of entitlement to do whatever one wishes to other people,” he said. “This is scheming, manipulative, lying, evil. This is not really about mental illness.”

Through a secretary in his Newport Beach office, Dietz declined an interview request but wished us a happy new year.

In January 2001, 60 Minutes aired a profile on Dietz, billing him as the FBI's top consultant on serial killers. “[Dietz] is most adept at explaining what makes the criminal mind tick,” the show asserted. “His preparation for trial is legendary. Where other psychiatrists often testify in terms that confuse, Dietz instructs jurors with the simple details of a case. He insists on seeing every piece of evidence.”

The show also suggested Dietz is something of a Freudian, saying he believes people are inherently “instinctual and riddled with bad impulses” and this negative outlook on the human condition was developed when he “discovered a book about forensic medicine filled with ghastly pictures.”

Dietz also advises Fortune 500 companies on how to spot potential psychopaths among their employees—before they go postal. The improbable list includes almost everyone you work with.

“Some [potential psychos] are going to be going to the union with grievances,” Deitz told 60 Minutes. “Some are going to be going out on disability. Some are going to fake a workers' comp injury. Some are going to be lousy performers…. Some are going to threaten to kill the boss. And one might even shoot people up. But we can tell which ones are going to be a pain in the neck if you don't intervene.”

In addition to his hectic schedule of spotting future spree-killers, Dietz has taught at several universities, including Harvard, Johns Hopkins and UCLA. He's so busy in fact, that in his 60 Minutes interview, Dietz boasted he doesn't have time to actually see patients. “A lot of it is very boring,” he explained. “Treating private psychiatric patients … means listening endlessly to people with fairly normal lives whine about why their lives aren't as great as they wished.”