COLUMN ONE : Probing the Dark Side of the Mind : Psychiatrist Park Dietz helps catch and convict criminals by unraveling twists of human behavior. Stalkers and serial killers are among his specialties.

It is a dark world that Dr. Park Dietz inhabits, a landscape of sexual sadist killers, psychopaths, a failed presidential assassin, an actress stalker and one world-famous necrophiliac-cannibal.

As America’s best-known forensic psychiatrist, Dietz is part of an elite fraternity of specialists so small that there is virtually no competition. How many authorities do we need on why people push others to their death on New York subways? He spent a year studying this.

Dietz is the FBI’s premier shrink, helping agents nab serial killers. He is an often-published researcher, he counsels celebrities about how to dodge crazed fans and he tells corporations how to prevent mass slayings in offices. He has been quoted as an expert on pornography, product tampering and erotomania, in which a person has delusions of love from others. His cases have included Jeffrey Dahmer and John Hinckley Jr.

Legend has it that Dietz is so deft at gazing into the criminally ill mind to help catch murderers that he inspired author Thomas Harris, who created the brilliant killer Dr. Hannibal Lecter in “Silence of the Lambs.”

Although highly regarded nationally by the psychiatric and law enforcement communities, Dietz, 45, occasionally has been dogged by controversy. He took heat during Clarence Thomas’ Supreme Court confirmation hearings--most people now say unfairly--for meeting with Sen. John C. Danforth (R-Mo.), who sought Dietz’s help in trying to discredit Anita Hill. Dietz said he was asked to testify before the Judiciary Committee but balked, citing professional ethics.

And a few defense attorneys have concerns that he mostly works for one side--the prosecution--as an expert witness. His fees--in the case of Dahmer, $3,000 a day--provoked one attorney to call Dietz a hired gun.

His supporters would argue that all professional witnesses are paid, and Dietz is worth every penny.

“His strengths are his intelligence and his common sense,” said FBI Agent Ron Hazelwood, a longtime colleague and friend. “I frequently find that the two don’t go hand in hand. He has this ability to speak to different types of groups--mental health groups, a jury, a police officer--and he’s able to relate to all levels.

“I might ask one psychiatrist to tell me something about a killer, and he might say, ‘Well he’s an insomniac.’ And he’ll maybe give you some medical jargon,” Hazelwood said. “Park (Dietz) will say: ‘He’s nocturnal, and you will find him at places that are only open at night.’ He tells you something in a way that you can use.”

Dietz, who is in private practice, mostly works behind the scenes. An FBI agent or a prosecutor may call him with details of a crime or suspect and ask Dietz to give his take on the kind of person they should be hunting.

When a southern federal judge and a civil rights lawyer were killed by mail bombs in 1991, Dietz was brought in. By studying the crimes, he said he was able to figure out “what the heck this guy was doing,” theorize why he was doing it, and help detectives catch the killer, Roy Moody.

These days, Dietz is devoting more time to the prevention of mass violence in the workplace. Every office gun battle, he says, every time an enraged or disgruntled employee has opened fire, could have been prevented. Somebody always knew that the killer was potentially lethal.

That’s how the hard-boiled Dietz sees the world: 5 million psychopaths are roaming the country, bumping our shopping carts and waiting behind us at the red light.

Once confident that he was unscathed by the subjects of his work, Dietz has come to understand that, despite the cool whisper of his cuff-linked exterior, his work bleeds into his personal life.

He chain-chews nicotine gum. He has made sure that his wife hits the bull’s-eye with a gun. And how many fathers wait for a Disneyland ride with their son by playing “Spot the Psycho?”

After years of threats from the deranged and disturbed he has helped put away as an expert witness, Dietz plays it safe. He is an award-winning marksman. He works in a high-security office. He refuses to be quoted about his family or say much about his personal life.

“I only recently realized that it all has an effect on me,” Dietz said with a sigh, pressing together all 10 fingertips, gazing out the glass walls of his office. “It gives me an entirely different outlook on humanity, what I expect will happen.”

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Like a lot of college roommates, Park Dietz and Greg Milmoe bonded over their love for beer, Ayn Rand books and their Cornell fraternity. Even then, Milmoe said, Dietz was an original.

It was only later that Milmoe discovered that Dietz had “the best collection of pornography available. Many of us would be reading pornography for the prurient interest, and here Park would be reading it as a scholar ,” said Milmoe, a New York corporate and securities attorney.

“He was a dyed-in-the-wool preppy conservative when I met him. He wore polished penny loafers, a suit and tie and was a stuffed pompous ass,” Milmoe said, laughing, “but a very smart one. . . . (He) had the ability to charm people. . . While chatting with you, you are the most important person in the world, and it is a talent he has cultivated professionally.”

With a doctor father and grandfather, premed student Dietz felt the pull of family destiny. Even then, he was “fascinated with the macabre, the twisted, the masochistic,” Milmoe recalled. “He had all the writings of Marquis de Sade.”

In 1969, Dietz had an epiphany. It came in the campus bookstore, as he leafed through a book called “Forensic Medicine” by Keith Simpson. The impact was huge, Dietz said, “because it was about unspeakable things people did.”

Dietz was riveted by a stark black-and-white photo of a nude man who had hanged himself from a tree, pornography fanned out on the leaves beneath his dangling body. The technical term: autoerotic asphyxiation. The picture was unflinchingly grisly. And Dietz knew then that the question echoing in his head-- Why did someone do this?--would guide his future.

“I got interested in electrocution, homicide cases, all kinds of really bizarre stuff, infanticide--when a mom kills her baby within its first year--that kind of thing,” Dietz said in a tone one might use to discuss the flu. “I was majoring in medicine, but my secret agenda was to relate everything to crime.”

After finishing his undergraduate degree in psychology in 1970, Dietz attended Johns Hopkins University School of Medicine, where he earned his M.D., and a master’s degree in public health by 1975. He would return in 1984 to earn a Ph.D. in sociology because, as Hazelwood said, “Park wanted to stifle criticism from sociologists.”

“Park will get interested in a subject, and he will pursue that to the point where he could have written a doctoral dissertation,” said Hazelwood, a sex crimes expert in the FBI Academy’s elite Behavioral Science Unit and National Center for the Analysis of Violent Crime.

Dietz and Hazelwood go back 14 years, to a time when psychiatry and cops did not mix. “We thought they were from Mars,” Hazelwood said, “and they thought we were from Mars.”

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It was his study of stalkers that first put Dietz in the limelight; his most famous case came 12 years ago with the man who tried to kill President Ronald Reagan.

Would-be assassin John W. Hinckley Jr. was obsessed with trying to impress actress Jodie Foster. He was arrested and tried in the 1981 shooting of four people including Reagan and White House spokesman James Brady.

As the prosecution’s star witness, Dietz interviewed Hinckley and examined evidence, including a letter to Foster. He concluded that Hinckley knew what he was doing, knew it was wrong and thus was responsible for his acts. Dietz testified that Hinckley was not criminally insane. The jury found that he was.

Dietz was thunderstruck. “It was a terrible disappointment,” he said, “but also a case in which I learned not to let the jury verdict be the basis for judging my performance.”

Still, “I just remember hearing the verdict and crying. I had to call Sarah Brady and tell her that the jury found Hinckley was not responsible for what he did.”

Although he is an expert on stalking, Dietz has no patience with celebrities. He chooses to counsel only security consultants, not the stars themselves. They don’t listen to advice, he says, and they refuse to recognize that they cannot act like normal people.

He has done the nation’s largest research project on stalking for the Department of Justice, examining scores of letters and other documents. Many in the field admire Dietz.

“He has an extraordinary intuition,” said Gavin deBecker, security consultant to Hollywood stars. “More than just his testimony in court is his interview style. He brought out things in Dahmer that turned out for everyone to be critical for people to know. He brought out the human aspect. . . . What Park has done is to connect people to these defendants in a way that makes them human beings, and without that you can’t know them well enough to render any kind of decision.”

*

There have been numerous murder trials, plenty of accused killers examined. But the most fascinating to Dietz, and the most celebrated, was Jeffrey Dahmer.

In January, 1992, Dietz was hired by the state of Wisconsin to examine the confessed serial killer, who lured 15 men to his apartment, then drugged and killed them, in many cases having sex with the bodies and eating parts of them.

Dahmer admitted the killings, so the only issue was whether to accept his plea that he was criminally insane--hence not responsible for his actions--at the time of the murders. This decision would determine whether Dahmer would be imprisoned or hospitalized.

After days of interviews with Dahmer, visits to his apartment building and the gay bars where he met many of his victims and examination of other evidence, Dietz concluded that Dahmer was not criminally insane as defined by Wisconsin law, and was responsible for his acts.

“I found him responsible for a number of things, but there were two points that had the greatest impact for public perception or at least a jury,” Dietz said. “And they were that he used a condom, and that he had no particular desire or interest to kill them and had to get himself drunk to overcome the revulsion of the killing.”

Even Dahmer’s attorney calls Dietz brilliant on the witness stand for the way he explained to jurors the legal versus the medical definition of insanity and of personality disorders, which is what they deemed Dahmer’s perversions.

“Dr. Dietz, in my opinion, is extraordinarily first-rate,” said Gerald P. Boyle, the Milwaukee attorney who represented Dahmer. “I knew from his writings that . . . no one has been able to persuade him that (grave sexual) disorders can be insanity under the law.

“But he’s extraordinary on the witness stand,” Boyle added. “He’s a hall of famer. . . . As an advocate, I disagreed with him, but I can’t fault him in any way.”

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Dietz’s work on Betty Broderick’s second trial, a high-profile made-for-TV event, draws contrasting views from the two sides.

Dietz, who did not interview the former San Diego doctor’s wife, nevertheless examined psychiatric reports and studied other case information. He testified that Broderick was capable of intending to shoot her ex-husband and his new wife in their bedroom. The jury found Broderick guilty of second-degree murder.

“So the jury completely rejected his testimony in that trial, because if they had accepted his testimony they’d have had to find her guilty of first-degree murder,” said prominent Irvine defense attorney Jack Earley, who represented Broderick.

Although he called the expertise Dietz has in certain areas valuable, he views Dietz as “a hired gun,” who like most expert witnesses is paid to testify. The problem, to Earley, is how much more he believes Dietz gets paid than other witnesses, casting an impression that Dietz has to deliver the opinion the prosecution essentially bought.

In the Broderick case, which some have argued did not hinge upon psychiatric testimony anyway, Earley said Dietz “just ignored the defense evidence. He’s a very strong professional witness. You have to pay the man his due, he’s a battler on the witness stand. . . And all the prosecutor wants is someone who will stand by his opinion.”

Kerry Wells, the San Diego deputy district attorney who prosecuted Broderick, scoffed. “I would argue that the jury did buy what Park Dietz was saying. Instead of voluntary manslaughter, they did convict her of murder. Second-degree just means she didn’t plan it ahead of time.”

He said claims that the $50,000 fee he paid Dietz tainted his testimony were ridiculous. “I couldn’t have bought that testimony any more than Jack Earley bought the testimony of his experts.”

Dahmer’s attorney, Boyle, agreed. Yes, Dietz was paid $39,000 for his testimony in the Dahmer case, he said, but Boyle believes that the forensic psychiatrist would never testify to something he was not convinced of.

“When you get to this level of professionals, they are so highly touted by their peers nationally,” Boyle said, “that they are . . . incapable of being bought.”

*

These days, many Dietz clients are Fortune 500 companies hoping to ward off violence by disgruntled employees. Such incidents have increased “rather dramatically,” and Dietz says about 5% of America’s work force is clinically depressed, a bad omen.

He says the U.S. Postal Service and other employers have failed to recognize and defuse potential problems among their workers. But some companies are realizing that money is better spent investing in ways to spot and handle combustible situations, instead of “mopping up” if disaster strikes.

He sees “ironic tension” in his relationship with the media, which he blames for fueling many crimes, such as product tampering, the syringe-in-the-soda hoax a recent case in point. He is highly critical of the media’s coverage of the controversial Attorney General’s Commission on Pornography, on which he served in 1985-86. And on broader issues, such as gun control, he diagnoses the country’s news coverage as hoplophobia: a fear of weapons.

Still, he recognizes the symbiosis involved.

“My work very much depends on the media, because my work is based on cases that would not happen without the media,” he said.

In late August, a crew from the Arts & Entertainment network filmed a lengthy interview with him about stalkers for a documentary, “Murderers Among Us,” in which he delivered two hours of pure Park Dietz--erudite and commanding in his expensive-looking black suit.

“If you ever invite Park to a dinner party, you need not have any other entertainment,” former roommate Milmoe said with a chuckle.

Dietz dismisses any celebrity appeal. “If I’m at a cocktail party and someone asks what I do, they listen, but after a few sentences,” he said with a smile, “they start to back away.”

*

Friends say that Dietz keeps his emotional balance with the help of his wife, a former lobbyist in Washington, whose intelligence and dry humor are a good match for him.

He points out that much of his work involves poring over police and court records, psychiatric transcripts and other after-the-crime reports. So becoming overwhelmed with the knowledge of his subjects’ despicable acts “isn’t usually a problem in dealing with the material as I deal with it.”

There are two exceptions: Visuals of mutilated children and sound recordings of torture victims.

After years of gazing into the worst of the human soul, he said, “I’ve learned there’s a cumulative effect on me.” It has left him with an admittedly jaded view of the world, but Dietz believes he simply sees people for what they are.

He also believes that people refuse to acknowledge responsibility for protecting themselves. “Self-defense is solely one individual’s responsibility, no one else’s.

“I think I’m one of the realists,” he said. “I think the rest of you wear rose-tinted glasses that serve your psychiatric needs well. And then you wonder why your child was molested by the nice man who offered to help your kids, or why your daughter was murdered by the nice boy who you did not insist on being introduced to, or why your neighbor with the unlocked door was murdered during the night. None of these are mysteries to me.”