DALLAS -- The director of the Dallas Museum of Art has resigned in the wake of his arrest on charges of public lewdness for allegedly fondling an undercover police officer.

Richard Brettell, considered a rising star in the art world, stepped down from his post last week at a time when the museum is raising funds to complete a $55 million expansion.

Brettell was arrested in October as part of a police sting that targeted homosexual activity in public parks. Early last month he pleaded no contest to the misdemeanor charges and was put on probation for one year. At the time he asked to be placed on temporary leave "to protect the museum from continued publicity."

Sources close to the museum's board said the group was divided about whether to allow Brettell to stay on until the controversy died down or ask for his resignation.

In a statement praising Brettell, the board made no reference to the incident. Referring to the new wing, President Vin Prothro said Thursday, "Without his tireless energy and artistic vision this project would not have happened."

"A resignation -- no matter whose or what reason -- is always a sad event," Brettell said in a statement. "But in this case, the best interests of a great museum have been kept firmly in mind."

Brettell said he and his wife, Caroline, plan to stay in Dallas "for the time being." He will remain a consultant to the museum until the wing's scheduled opening in September.

A former curator at the Art Institute of Chicago, Brettell, 44, was considered an important hire for the Dallas museum. "Rick was one of the best members of his generation, the next generation of young curators," said Art Institute Director James Woods in a recent interview. While in Chicago, Brettell organized such shows as "A Day in the Country: Impressionism and the French Landscape," which traveled to the Grand Palais in Paris, and "The Art of Paul Gauguin," which opened at Washington's National Gallery of Art in July 1988 before traveling to the Art Institute and the Grand Palais.

In Dallas, Brettell had just launched a major show on Camille Pissarro and had scheduled shows for 1994 (both going to the National Gallery) on children's art and Mexican Viceregal art.

It was shortly before the Pissarro opening in October that Brettell allegedly followed an undercover policeman into the bushes of a park in the Oak Lawn neighborhood and, as the Dallas Morning News reported, stood "face to face" with him "before rubbing the officer's genitals through his pants." The arrest was part of an extensive sting operation in which nearly 200 people were charged with similar crimes.

The arrest has provoked controversy outside the art world, causing some here to question the motives behind the sting.

"Don't the police have anything better to do than gay-bashing?" asked Joe Cook, northern regional director of the American Civil Liberties Union of Texas, of a reporter at the time of the arrest. Cook said recently the ACLU is considering a lawsuit based on the police department's investigative techniques, which included surveillance of individuals in the parks.

Others see a broader story here: the conflicts between Old Dallas and New Dallas. Veteran Texas observer and newspaper columnist Molly Ivins calls the contradiction "a schizophrenia" between the town that "presents itself as a place open to experimentation, and the old, repressive, authoritarian atmosphere."

She cited another recent case in which a Dallas judge gave a light sentence to a double-murderer because the victims were "just queers."

"What can I say about Dallas? There it is," she concluded.

This is not the first time the art world has mirrored such contradictions here. Despite its current penchant for contemporary art, the Dallas art community has always been conservative -- at times swinging far to the right. In the '50s, a movement arose to rid the Dallas Museum of Art of its work by "communist" artists. People were calling Mexican muralist Rufino Tamayo a communist until the beleaguered museum director pointed out that Tamayo was a millionaire. But Picasso was banned from the museum because he was a "confessed communist."