SAN FRANCISCO -- The bald man in a black jacket limped stiff-leggedly down the street, his left hand holding an umbrella, his right hand pressed to his thigh.

Police officer Kent Haas, summoned from a routine traffic stop by a "shots fired" call to 911, pulled his darkened patrol car over and ordered the limping man to freeze.

Instead, Haas told a grand jury, the suspect ducked behind a car and tugged at his waistband, where a rifle stock shone in the light of a street lamp.

"Stop or I'll shoot," Haas barked. He was six feet away.

Most of the rifle was now out of the pants, Haas recalled, but the barrel seemed to snag on something. The officer assumed his firing stance, feet apart, gun leveled.

Finally, the man in black looked up.

"Okay," he said. "Okay, I'll stop."

On the hallway floor inside the rented house on 21 Mohawk Ave., Corte Madera, police found Artie Mitchell, 45, his dark beard turning a wet red. Of the seven bullets that had been fired -- empty casings littered the floor -- three had found Artie. It was the one in the right eye that did him in. Beer still fizzed from a spilled bottle in the hall.

The suspect police took into custody last Feb. 27 -- a bald man with a pocket full of .22 shells and a smoking gun in his pants leg -- was 47-year-old Jim Mitchell, Artie's brother.

San Francisco is not an ordinary place; ordinary protocols of conduct and of social status do not always apply. And so it is that the man accused of fratricide is a philanthropist, an environmentalist, a humanitarian, a civic leader ... and a celebrity pornographer. And so it is also that although he does not deny firing the shots that killed his brother, he contends he was acting not out of madness or malice or greed, but out of love. His lawyer says Artie Mitchell's death was a "tragic accident."

The case is no less bizarre, no less filled with paradox, than were the lives of the Mitchell brothers. Jim chauffeured for neighborhood kids; Artie coached Little League. And yet, together they were porn pioneers, producing the 1974 crossover skin-flick "Behind the Green Door" that launched a multi-million dollar mainstream flesh industry. Porn, with panache.

In a bail-hearing declaration for Jim Mitchell, journalist Warren Hinckle said: "He has been unsparingly generous in his good works in the community, and San Franciscans of every complexion are keen to see him return to active civic life for the good of the commonweal"; he sounded as if he were describing a social worker, rather than the proprietor of the city's most notorious porn theaters. "I would trust my life, and the lives of my children, to him without a moment's hesitation."

The district attorney says the facts will show that the crime was coldblooded: Why else would Jim Mitchell have parked his car around the corner three blocks away, and slashed the tires on Artie's car? Jim, he says, was trying to rid himself of his besotted wastrel brother, whose increasingly erratic behavior was threatening to destroy their business and their family.

Defense attorney Stuart Buckley counters that Jim's intent was "to scare, not kill," that he was exercising a little tough love to set straight a debauched and reckless younger brother who was losing his mind to alcohol. In the weeks before the killing, "Party Artie" had been banned from his own theater for firing a shot into the ceiling in a drunken rage; his accountant rejected his own checks as forgeries, so addled was the signature.

The facts that are expected to emerge in the trial of Jim Mitchell, scheduled to begin this week, would neatly fit one of the Mitchell brothers' high-class hard-core movies. It has sex and sleaze and booze, and oodles of irony.

Too Close for Comfort

Together. That's the word that's always been used with the Mitchells. Together they helped revolutionize porn and fought for free speech, in the end standing proud on the city's social scene, hanging out with politicians and writers after 20 years of pummeling by the local authorities.

They gave $6,000 so volunteers could take brunch to the AIDS ward at San Francisco General for a year; they dropped $20,000 on the first Earth Day for murals of humpback whales and a rain forest. They brought their mother -- Georgia Mae Mitchell, a retired elementary school teacher who attended their obscenity trials and movie parties alike -- a $130,000 home near Sacramento, and cut her in on 10 percent of their business.

The brothers' identities were inseparable, yet separate.

They competed at everything. Artie was always upset that Jim had been arrested one more time than he had (189 to 190; the gap was widened by the murder charge). A year ago, when Artie's 17-year-old son nearly drowned in the riptide off Ocean Beach, Jim unhesitatingly followed Artie into the treacherous water to save him.

Artie wore his heart on his sleeve; he buried his head in his hands while watching the gulf war on TV. Jim was Mr. Business; to oppose the war he wrote checks to back an alternative paper.

Near the end, friends and family were calling Artie, urging him to curb his drinking, check into a treatment program.

On Feb. 27, the last day of his life, Artie called Jim at his home here. I'm not the only one with a problem, the younger brother said to an answering machine. You have a problem, too, one that will eventually kill you.

Then he called back: "Don't you love your kids enough to stop smoking?"

It was childlike behavior: defensive, evasive, petulant. But it did something to Jim, who decided it was time to pay Artie a visit.

He drove his 1991 Ford Explorer across the Golden Gate Bridge to Artie's rented house in Corte Madera, where, for reasons only he knows, he parked three blocks away.

Legend of the Porn Princes

The Pacific Ocean washes into the San Francisco Bay past spectacular, jutting mountains, but it's a spent force by the time it reaches the Sacramento River delta at the other end of the inlet. The river wends its way past nondescript town after nondescript town, and Antioch could be as easily missed as noticed.

Now a growing bedroom community of 70,000, Antioch was a mill town of 7,000 people back in the 1950s, when James Lloyd and Arthur Jay Mitchell were growing up.

Artie was a rebel early, walking home for lunch because he didn't like the fare at school -- even though his parents had already paid for it. His dad was usually there asleep after a long night playing legal low-ball and illegal other card games to support his family. If Artie would turn out to resemble his father in many ways, Jim took after his mother: steady, protective and serious -- at least compared with Artie.

In the Mitchell family mythology -- a story repeated over the years to reporters, and reprinted endlessly -- the brothers were watching a cheap stag film at an Antioch nightspot when one turned to the other and observed, "Hey, bub, an ol' boy could make himself a lot of money with these movies."

There was almost certainly a more prosaic inspiration: Friends say that while in college, Jim was working nights in a porn theater, and saw how much money utter trash brought in. If men would pay to hunch furtively in back rooms to see grainy, blurry, amateurishly simulated scenes of intercourse filmed in hotel rooms and backed by cheesy rock soundtracks, what would they spend to watch professionally filmed, gynecologically precise movies in comfortable surroundings? When Artie came home from the service, the boys were in business.

Using a 16-millimeter Bolex camera, the brothers produced 11-minute soft-core loops, earning a legendary $6 profit on the first one.

The O'Farrell Theatre opened on July 4, 1969, a date with both libertarian and libidinal connotations. Two hundred plush seats with good-quality sound and lighting equipment. It was an instant financial success. It was also raided within three weeks.

At Jim's first trial, the DA charged that "porny," as a local paper referred to it, had become a $5-million-a-year business with two dozen theaters in San Francisco alone, and that Mitchell was an evil force behind it all.

The jury deadlocked. "We're clean-cut all-American boys," Jim said afterward. "We're going to stick with clean-cut little {sex} movies."

And, indeed, they did.

In 1971 Artie went on trial for the first time, along with veteran Jim, for the 10-minute opus "Glowy Flesh." After 10 hours, the jury came back with a guilty verdict -- the brothers' sole obscenity conviction in their long career of arrests. They got probation.

Then the city tried another tactic, passing a regulation requiring porn theaters to be licensed. At a police commission hearing for an application, 15 witnesses rose to vouch for the brothers' good standing in the community. Jim's wife explained the support in a succinct statement that underscored the city's difficulty in attempting to regulate porn palaces out of existence:

"People go there," she said, "because they enjoy it."

They got the license.

The 'Green Door'

In 1972, they made "Behind the Green Door," and the big time. Filmed at the then-unheard-of price of $60,000, the film went on to become the highest-grossing porn movie in history, raking in at least $25 million.

Flat-chested and with stringy dirty-blond hair, Marilyn Chambers couldn't get even a supporting role in an adult video today without a breast and bleach job; but in the early '70s, her panting and moaning came off as a sincere and assertive sexuality. She actually seemed to be having a good time.

Gloria Leonard, a former porn actress who now works with the anti-censorship Adult Video Association, improbably praises "Behind the Green Door" and other Mitchell brothers films as feminist milestones.

"Women not only like sex, but could dictate where and when," she said of the films. "It showed a woman in charge of her own sexuality."

The film had been out for a while when it was to open in New York. Jim called the wire services to let them know that the young woman cheek-to-cheek with a baby on the Ivory Snow soap box was their leading lady. This created a minor sensation, and a major box office hit.

By 1974 their empire stretched to 11 theaters and movie houses. Some of the more memorable works in the Mitchell oeuvre: "Resurrection of Eve," "Inside Marilyn Chambers" and "Autobiography of a Flea." After a judge observed that they would offend the community standards of Sodom and Gomorrah, they made a movie by that name, which at $450,000 became the most expensive porn production ever.

After 1978 the brothers sold many of their theaters and made only two movies. Some say they didn't want to compromise their standards and compete with the videotape glut that ended the Golden Age of Porn at the turn of the decade; suddenly every guy with a camcorder and an obliging girlfriend was a producer.

But the brothers' mid-'80s swan songs were typical Mitchell product -- bizarre, even by the standards of the time. "The Grafenberg Spot," a "six-day wonder" made to pay off legal bills, was about women who ejaculate. The special effects seemed to involve garden hoses.

"Behind the Green Door: The Sequel" was the first safe-sex film. Its star was Missy Manners, nee Elisa Florez, whose resume was weird even for a Mitchell starlet: Georgetown poli-sci major, Senate page, intern and receptionist for Utah's Orrin Hatch, Republican National Committee staffer and Ronald Reagan campaigner. (It became Missy when Washington Post columnist Judith "Miss Manners" Martin obtained a cease-and-desist order.)

Like the first "Green Door," the sequel became better known for its star than for anything else. Which was just as well, since the 1986 movie -- a smorgasbord of latex and lubricants -- proved to be just as unsexy as the concept sounds. But, it could be argued, the brothers finally lived up to a boast Artie made at a public hearing 15 years earlier:

"Our films are socially redeeming."

Reach Out & Touch Someone

"Hi, would you like some company?" suggests the blonde in the pale silk garters and G-string, bending forward invitingly. Nearby similarly almost-dressed women sit on men's laps.

Others ply the plush aisles of the O'Farrell Theatre, clutching wads of tips lest anyone assume that the $25 cover charge ($15 before noon) covers much. Nonalcoholic beer is $2; there is no smoking, and no liquor.

This is the enterprise to which Jim and Artie devoted most of their energies during the 1980s, and from which they reaped most of their profits.

Buses disgorge Japanese tourists straight from the airport; office workers take long lunches and know the show schedule by heart.

Besides the strobe-lit, disco-backed dancers, the O'Farrell features a garden of voyeuristic delights: the Ultra Room, New York Live, the Shower Show. Whether your taste runs to the cinematic, sapphic or leather, you can find it at the theater. Or buy it on videotape in the gift shop.

But the real show was often in the upstairs office, where the brothers kept a well-stocked refrigerator and comfortable digs for friends to drop in on. A pool table took pride of place in the room, alongside a Wurlitzer jukebox and a $1,000 stuffed moose head. A note suspending Artie from high school for drinking hung on a wall.

Former dancers speak highly of the place. "They have the best sexual entertainment theater in the country," says Debi Sundahl, who danced there for four years and now publishes a magazine of lesbian erotica, On Our Backs. "It was really classy. I loved working there."

She says that at any given time maybe a third of the 75 dancers are putting themselves through school, while many others are struggling writers and artists.

On Feb. 1, 1985, Marilyn Chambers strode onto the stage at the O'Farrell and sang two country-western songs. But as one might expect in a show called "Feel the Magic," Chambers also did a little more. Two dozen officers raided the midnight show and arrested her for "prostitution."

Their version of what went on in the theater that night: "sexual contact" with 20 men.

Chambers's explanation: "These people have been my fans for years and it's a thrill for them to touch me up close."

Chambers got released on bail several hours later, after the police queued up to be photographed with her, and no charges were ever filed.

Even Mayor Dianne Feinstein, no fan of the Mitchells for their habit of putting her unlisted phone number on their marquee ("For a Good Time, Call ..."), labeled the bust silly.

Playing Hardball

The Mitchell brothers' personal lives were no more placid than their professional ones.

Jim and Adrienne Mitchell separated after three years of marriage in 1974. In the divorce, Jim played hardball.

At a deposition, Adrienne broke down. "He wins," she sobbed. "He warned me. He said, 'Adrienne, if you don't take my offer I'm going to make it so miserable for you.' ... He wins. He's stronger. He always wanted to be stronger. He wins. I want my life back."

This was the Jim Mitchell few talk about, the driven, determined taskmaster.

His next marriage lasted seven years and produced four children by the time it broke up in 1986; the second split was much more civil, with Mary Jane Mitchell vouching for him years later during his bail hearing. The children are now ages 6 to 13. Mary Jane begged the judge to release Jim on bail because the children missed him.

Artie was no luckier in love.

In 1976, he was sleeping in his office at the theater. It had not been a good year: His six-year marriage to Meredith Bradford broke up, an employee skipped town with several hundred thousand dollars of the Mitchells's money. The future Karen Mitchell was hired to cater the set of "Autobiography of a Flea."

After finding out that the charming guy in the tweed racing cap was living on chicken noodle soup and Cheerios, the 18-year-old Karen invited him home for a meal one day; he never left. After living together for three years, Artie and Karen were married and moved to the Farm, 5.8 acres they purchased in bucolic Canyon in Contra Costa County for $400,000. They lived in a cabin, with water from a well and a menagerie of chickens and goats and peacocks.

Karen went to work in the theater, doing everything, she says, from hammering studs into the wall of the bondage-theme Ultra Room to doing the payroll and getting the company into a health insurance program.

When the end came in 1983 it was the stuff of Divorce Court From Hell: Artie got his monthly child support payments reduced. Karen Mitchell got a restraining order requiring that Artie not drink around the kids. He said she beat the kids; she said he ate mushrooms and shot heroin.

In court papers, Karen Mitchell claims Artie bragged about paying off judges, that he once arranged for her to be raped as punishment, that he once tried to strangle her in front of the children.

Without question, in the months before his death, Artie's wild living and prodigious consumption of drugs and alcohol were taking a toll on himself and on his family. His behavior went from erratic to bizarre.

On Feb. 16, Artie packed 8-year-old Caleb into his 1990 Dodge Colt and drove to the Kaiser Hospital emergency room, where he insisted that his son's finger was injured. A nurse said nothing was wrong. Ruddy and angry, Mitchell demanded treatment, throwing $100 bills around. The nurse called a cop, who, seeing Artie off balance and slurring his words, arrested him for causing a disturbance.

In his report, the officer noted that Mitchell was a "danger" to his son and "too drunk to care for {him}self." ... Out of Control

Artie and Julie Bajo, a 27-year-old former stripper, had been dating for nine months; in January, she moved into the ramshackle white stucco house on Mohawk Avenue with the younger Mitchell kids tearing through it and the older ones bringing friends by to drink beer with Dad.

Artie's lifestyle took a little getting used to, Bajo says. She learned to sleep through the sound of him heaving into the toilet at night, and to ignore his knocking back a few beers for breakfast the next morning.

Bajo criticizes Artie's friends and family, who, she says, seemed to be plotting to force him into a treatment program, instead of giving him the love and reassurance he really needed. "Artie's only friends were booze, drugs and his children and me," she said.

A week before he died, Bajo says, Artie told her that Jim wanted to break up the business.

"That's fine with me," she heard him say one day on the phone. "I don't have a problem with that, as long as I, you know, I get a fair shake."

But over the next week, she says, he grew madder and madder, making threats to people and taunting Jim -- calling him a washed-up old man. Bajo phoned Jim to tell him how worried she was about Artie. She says Jim brushed her off. (Karen Mitchell says she made a similar call, and got a similar response.)

On Feb. 27, Bajo heard Artie talking to his mother on the phone. "I'm not the only son with a problem," he said, according to Bajo. "If Jim stops smoking, I'll stop drinking."

He hung up. "I'm tired of everyone telling me I have a problem," Artie muttered. The Last Night

Julie Bajo took off her contacts, removed her makeup and brushed her teeth before turning off the lights in the house and climbing into bed with Artie. As she ran her hands over his beard and chest, they talked of getting away, she says, of lying in the sun in Mexico.

"He said he had put in 21 years and he deserved at least six months to a year off," she recalls.

The familiar creak of the front door came through the quiet house. "Artie's slogan was 'my door is always open,' in case somebody needed a place to stay in the middle of the night or something," Bajo said.

Then it slammed shut and something started bumping through the hall, making all kinds of noise. They sprang from the bed and Artie turned on the lights. Bajo grabbed the phone and stepped into her closet, closing the door except for a crack. She dialed 911.

A gunshot cracked through the hall, then another. Artie asked for a bat. She looked at her belt hanging in the closet. That's all I have, she thought.

"Gimme some pants," he said. She handed him a pair of green sweats and he picked up a not-quite-empty Heineken bottle and walked into the dark hall.

There were shots and a scream and more shots. Then nothing.

The Aftermath

If Artie's life had been riotous and indecorous, his death and its aftermath have been no less so.

Julie Bajo is suing Jim for half a million for emotional and physical distress caused by the shooting. Karen Mitchell is also suing Jim, in the name of her three children, seeking compensation for the wrongful death of their father. She is also suing Artie's estate for the support of her twins, whom she claims Artie fathered after their divorce. She wants to use the coroner's blood sample to establish paternity. (Relatives say Artie had a vasectomy in 1986 and couldn't have fathered the 17-month-old boys.)

A couple of days after Artie's death, a neighbor reported to the police that Karen Mitchell had broken the police seal on the house and carted off, among other things, paintings, a VCR, a computer, and matching fax machines Artie had recently purchased for himself and Jim. She said it was stuff the kids should get, but ended up returning much of it at the behest of the police.

Then there are the movie options she's shopping around with her Hollywood attorney.

Life at the O'Farrell, at least downstairs, seems to go on much as before, with the experienced staff closing the door for only a couple of days of mourning.

Two psychiatrists (including Martin Blinder, creator of the "Twinkie defense" for murderer Dan White) found Jim Mitchell suicidal and clinically depressed.

"Tell those little children I didn't mean to hurt their father," Jim sobbed recently to a visitor.

What did he mean to do?

In court papers, Jim's lawyers have suggested he wanted to scare his brother straight, that he wanted to show, by example, how insane Artie was acting. Altogether, an uncharacteristically harebrained and dangerous plan to have been concocted by the careful brother, the businesslike brother, the methodical brother.

And yet. The defense points out there was no financial incentive for Jim to murder Artie -- in fact, there was a disincentive at a time when the two were negotiating an amicable dissolution of their partnership. Artie's money -- and now, his share of the business -- will be divided among his six children.

And yet. Why not use blanks, if Jim's intent was merely to frighten?

And yet. Why slash his brother's tires, if he intended to leave him dead?

And yet. Why three shots to the body, if it was an accident?

The trial will unquestionably address these questions. Possible motives will be raised, and denied. Experts will testify. The truth may or may not surface.

"It wasn't a murder," flatly pronounces the Mitchells' childhood friend, Richard Lackey. "Jimmy just couldn't do that. It's impossible."

"Something happened there that no one will ever know."