A Washington area nudist group, driven from sunbathing on a remote beach on Virginia's Eastern Shore by a local law, is wrapping itself in the Constitution and challenging the prohibition.

In a lawsuit filed yesterday in U.S. District Court in Norfolk, the National Capital Naturists charges that Accomack County does not have the power to ban nudity on the beaches of Assateague Island. The county's law, enacted last summer, denies the nudists' constitutional rights of free expression and does not promote the health, safety and welfare of local residents, the lawsuit says.

"These people are trampling on our rights," said T.V. Stokes, president of the nudist organization. "We're not going to roll over and play dead."

Accomack officials vowed to fight the lawsuit. "We don't plan on backing down to them," said James C. Payne, chairman of the county Board of Supervisors.

Accomack Prosecutor Jon C. Poulson, one of the defendants in the suit, said, "The ordinance is constitutional and the ordinance is supported by the vast majority of the people here."

Since the county board passed a law designed to end nude bathing at Assateague, more than 50 nudists have been given summonses. Although the ordinance provides for fines up to $1,000, most of those arrested have been fined about $135, according to county authorities.

The 15-page lawsuit calls nudism "a worldwide social movement" that promotes a "wholesome and healthful lifestyle in Accomack County."

The suit maintains that residents of Accomack "have differing standards toward nudity" and that "at least one movie theater routinely displays films containing nudity in other than a wholesome manner."

Stokes, 57, said his group has raised more than $10,000 in the past six months to finance the lawsuit. He said the National Capital Naturists, incorporated in Virginia last year, has a mailing list of about 1,900 people.

Stokes said the group plans to stage a number of events at Assateague on the weekend of July 13 to celebrate the Ninth Annual National Nude Weekend. "I can't guarantee what'll happen," he said.