SAN FRANCISCO (CBS SF) — As promised, a small group of nudists on Friday re-filed a federal civil rights lawsuit challenging a city of San Francisco ban on nakedness on public streets, sidewalks and transit vehicles.

The nudist activists claim the law violates their right of free speech because police allegedly have enforced the ban selectively against them when they bare all for purposes of political protest, but not against people who participate in other types of nude events.

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The measure enacted by the Board of Supervisors last year went into effect on Feb. 1. First-time offenders can be punished by a fine of up to $100.

An earlier version of the lawsuit was dismissed on Jan. 29 by U.S. District Judge Edward Chen of San Francisco, who said that nudity in itself is not protected free speech because it “is not inherently expressive.”

But Chen said the activists could file an amended lawsuit after the law took effect if they wished to argue that the measure was enforced against them in a discriminatory way.

Friday was the deadline for submitting a revised lawsuit.

The amended suit adds a fifth plaintiff, Russell “Trey” Allen, to the previous four plaintiffs: Mitch Hightower, George Davis, Russell Mills and Oxane “Gypsy” Taub. All are San Francisco residents except Taub, who lives in Berkeley.

It names the city of San Francisco and the Police Department as defendants.

The suit asks for a judgment declaring the law unconstitutional as applied to the plaintiffs, as well as a temporary restraining order and preliminary injunction blocking enforcement of the law.

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No hearings have been set on the requests for orders blocking the measure.

Matt Dorsey, a spokesman for City Attorney Dennis Herrera, said, “We’re still in the process of reviewing this, and it would be premature for us to comment substantively.”

Dorsey said the city’s lawyers have until March 29 to file either a response to the new lawsuit or a request for dismissal.

The law authored by Supervisor Scott Wiener bans public nudity on streets and sidewalks, and in plazas, transit stations and vehicles, except in cases of children under the age of 5 and parades and fairs that have received permits.

Separate city laws restrict nudity in restaurants, public seating areas and parks.

The lawsuit says that Davis, Taub and Allen were arrested for nudity at a political rally held in front of City Hall on Feb. 1 to protest the law and that Davis was arrested during a nude artistic dance performance organized by the plaintiffs on Feb. 27.

By contrast, the lawsuit alleges, none of the plaintiffs or any other nude participants were arrested during a Feb. 17 film shooting and a March 9 nude bike ride organized by other groups.

“Defendants have taken every opportunity to strike at plaintiffs at events they organize, while apparently being struck by a feeling of obliviousness when it comes to events organized by others who are not part of this lawsuit,” the amended suit alleges.

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