THE O.J. SIMPSON MURDER TRIAL : Defense’s DNA Expert Is Called Brilliant, Offbeat : Profile: Colleagues say Nobel laureate who uses LSD and scandalizes scientific meetings loves theatrical behavior. D.A. may use his personal history and outrageous ways to attack his credibility.

SAN DIEGO —  Kary Mullis, the Nobel laureate and DNA expert who may testify for the defense in the O.J. Simpson case, is known in the scientific community for his brilliance, his iconoclasm and his sometimes outrageous ways.

Twelve years ago, he discovered a method of unlocking the secrets of DNA that led to such advances as genetic fingerprinting from tiny blood samples, the type of evidence that the prosecution hopes will convict Simpson. Defense lawyers, however, have indicated that Mullis will testify about the fallibility of DNA testing in criminal cases.

Since his discovery, Mullis has turned his back on Establishment science and academia, preferring instead to surf, skate, photograph naked women and pursue arcane topics such as cosmology and mysticism.

Prosecutors this week vowed to grill Mullis on “every aspect of his life which reflects on his credibility, competency and sobriety,” including his admitted use of LSD, his run-ins with other scientists, and his controversial view that HIV has not been proven to cause AIDS.

Although Mullis could not be reached for comment Tuesday, he has, in the past, expressed a dismissive disdain for critics of his behavior or offbeat ideas.

“I am not addicted to social approval,” he told The Times before he received the Nobel.

One piece of personal history that might be brought up would be a 1990 domestic violence case involving Mullis. Los Angeles Dist. Atty. Gil Garcetti has called the San Diego prosecutor who handled that case.

In 1990, Mullis was accused of five misdemeanor counts of beating his estranged wife on two occasions, including one incident in which he allegedly gave her a black eye. Prosecutors also contended that he tried to harass her into dropping the charges by leaving messages on her answering machine.

In a plea bargain, Mullis pleaded guilty to one count and was ordered to undergo counseling and attend Alcoholics Anonymous meetings. Mullis had 12 hours of counseling and attended 20 AA meetings, according to court records. After a year, the case was dismissed.

At age 50, the thrice-divorced Mullis lives in a tiny apartment across from Windansea Beach in La Jolla and the pump house made famous by Tom Wolfe in his paean to the Southern California surfing culture, “The Pump House Gang.”

Mullis has said he was drunk the morning that Nobel officials called to inform him that he was one of two winners of the 1993 prize for chemistry. He later went surfing.

When he went to Stockholm to pick up his prize, he is said to have scandalized the Swedish royal family by suggesting that he would hook up a teen-age princess with his son if he could have a third of the kingdom.

True or apocryphal, the Stockholm story is vintage Mullis: outrageous and nothing like what you would expect of a world-famous scientific thinker.

Mullis delights in telling how he became a heavy user of LSD as a graduate student at UC Berkeley after reading Aldous Huxley’s “Doors of Perception,” which extols the drug’s mind-expanding virtues. He says he still trips two or three times a year on LSD to “be reminded of the complexities of things.”

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He has joined a small band of renegade scientists who believe that the connection between HIV and AIDS has not been proven and that the federal government is wasting billions of dollars.

“Kary Mullis is a very ingenious fellow,” said Charles Thomas, a former Harvard University medical professor who now heads a biotechnology firm in San Diego. “But he’s so damnably anti-Establishmentarian, so antinomian that he puts a lot of people off.”

Henry Rapoport, one of Mullis’ doctoral dissertation professors at Berkeley and later one of his colleagues at Cetus Corp. when he made his DNA discovery, said he is not surprised that Mullis would take the stand in the Simpson case and fly in the face of scientific dogma that DNA testing can lead to proof in criminal cases.

“He’s skeptical, very questioning, very critical,” Rapoport said. “A more accepting person probably wouldn’t have made the discovery he did. If there was anyone willing to testify that DNA testing is not perfect, it would be Kary.”

Rapoport remembers Mullis as one of the most unusual graduate students he ever mentored. But he cautions against taking him at face value, including his claims about continued use of LSD.

“He has a bit of put-on artist and loves to engage in theater,” Rapoport said. Since winning the Nobel, which brought an award of $412,500, and a passel of other scientific prizes, Mullis’ chances for theater have been substantial.

A writer for Esquire reported that Mullis spent much of their interview trying to talk her into bed, on the theory that she could only get to know him well enough to write about him if they had sex.

She declined.

Beyond a keen interest in the opposite sex, Mullis’ passions include motorcycles, his cabin in Mendocino, playing guitar and country music. He is in high demand as a lecturer and consultant. A native of North Carolina, he retains his Southern accent and a gregarious, boyish, tousled-hair manner and loves to unleash provocative opinions.

He has no sympathy with environmentalists and likens them to the damnation-breathing Baptist ministers of his youth. He says he is undisturbed by predictions that pollution or global warming or a hole in the ozone could wipe out the human race.

For shock value, Mullis sometimes slips in slides of naked women bathed in psychedelic light during the middle of otherwise upright scientific lectures.

One audience that was unamused by the nude slides was at the 28th annual scientific meeting of the European Society for Clinical Investigation in Toledo, Spain.

John F. Martin, president of the society, wrote an outraged letter to Nature magazine, upbraiding Mullis for the slides and for using his lecture to discuss his view on HIV and AIDS and not his Nobel-winning discovery, called the polymerase chain reaction (PCR).

“His own explanation of the immunodeficiency syndrome was incoherent and insubstantial,” Martin wrote.

Mullis also accused scientists of widespread falsification of results to obtain grant funding and attacked several AIDS scientists by name. “The council . . . will not be inviting Mullis to speak at further meetings,” Martin wrote.

Mullis used a nude slide during a rambling speech to a gathering of Connect, a business program at UC San Diego dedicated to bringing together entrepreneurs and biotechnology scientists in need of financial backing. Audience members shifted uncomfortably in their seats.

A videotape was made for possible use on the campus television station. Investigators for Garcetti have been seeking a copy.

Mullis can be charming and his enthusiasm for science highly contagious. When a top science student from La Jolla High School asked for an autograph, he not only scribbled his name but talked to her at length about the discipline and glory of science.

“People expect me to be flaky and have odd ideas,” Mullis has said. “I do have odd ideas. I dabble in a lot of things, but I dabble seriously.”