Art Mitchell, 45, porno pioneer, was shot to death in Corte Madera, Calif., Feb. 27. His brother and partner, Jim, was arrested for murder when police allegedly caught him leaving the scene with two guns.

The Mitchell brothers had an early hit as producers with “Behind The Green Door,” starring Marilyn Chambers. They backed their production with an exhibition chain flagshipped by the controversial O’Farrell Theater in San Fran.

According to police, Art Mitchell was shot seven times in the head and body. Art’s girlfriend, Julie Bajo, a dancer at the theater, called the police.

Police say they arrested Jim Mitchell outside the house. He refused to talk and police declined to discuss a motive.

Friends said the pair recently had agreed to dissolve their partnership.

The Mitchells made their first porno pic shortly after leaving high school in Antioch, Calif. In 1969, they opened the 200-seat O’Farrell, which was considered plush compared with many tenderloin outlets screening adult pics. The explosion of “porno chic” made the O’Farrell into something of a landmark.

The brothers continued in production, becoming in 1971 one of the first makes of adult pics to upgrade to 35m and attempt full-length feature films with some a story line and production values.

By the standards at the time, Chambers was younger, fresher and a better actress that usual, and the Mitchells tailored “Green Door” to her talents. The producers also set another precedent by giving their leading lady financial participation in the picture.

By 1974, the Mitchells were operating 11 theaters. They also produced such pics as “Sodom And Gomorrah,” (1976), “Autobiography Of A Flea” and “The Grafenberg Spot.” In 1985 they made a safe-sex sequel to “Beyond The Green Door” (featuring condoms in all the lovemaking scenes) that received plenty of publicity but did not change adult filmmaking methods.

As their empire grew, the Mitchells were the subject of numerous obscenity prosecutions but were never jailed. The brothers were given six-month prison sentences once for contempt of court in a prostitution case, but the California Supreme Court twice overturned lower court decisions in the case.

With the waning of interest in porno, the Mitchells quit production and sold most of their theaters, retaining only the O’Farrell, which still presents a combination of film and live sex shows.

The brothers were in the news nearly a year ago following a near-drowning off Ocean Beach. Art was hospitalized for hypothermia after he and several family members were rescued from a dangerous rip tide off the coast. Art had tried to rescue Jim’s 17-year-old son, Storm, after several youngsters got caught in the tide. Jim used a surfboard to save Storm, and rescue swimmers pulled Art out of the water after about 30 minutes.

Survived by six children.

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