CHICAGO - JULY 30: Beach goers relax at North Avenue Beach July 30, 2008 in Chicago, Illinois. According to the National Resources Defense Council (NRDC) beaches in Illinois have the highest number of water samples exceeding safe bacterial levels in the nation. (Photo by Scott Olson/Getty Images) North Avenue Beach (File Photo: Scott Olson/Getty Images)

CHICAGO (CBS) — Demonstrators will gather at North Avenue Beach Sunday to protest against laws that forbid women from going topless.

The organization GoTopless plans to protest from noon to 5 p.m. at the North Avenue Beach. They will gather on the overpass over Lake Shore Drive north of Castaways Bar and Grill.

The protest event, which is now in its fifth year, proclaims that women have a constitutional right to go topless in public. It encourages equal opportunity by urging women to bare their breasts, and for bare-chested men to cover up with bikinis or bras.

Organizers complain that men and women are subjected to a double standard.

“It’s appalling that even female officials like the mayor of Asheville, North Carolina, are supporting the men who oppose topless gender equality,” GoTopless leader Sharon Aziza said in a news release. “They got where they are through gender equality. How can they deny that hard-earned right to other women?”

Laws governing whether women are permitted to go topless vary city by city. The State of New York permits women to go topless even in public areas, and the City of San Francisco has no laws against public nudity.

But Chicago does not permit any such things.

Under the city’s Municipal Code, it is illegal to “appear, bathe, sunbathe, walk or be in any public park, playground, beach or the waters adjacent thereto, or any school facility and the area adjacent thereto, or any municipal building and the areas adjacent thereto, or any public way within the City of Chicago” exposing “any portion of the breast at or below the upper edge of the areola thereof of any female person.”

The prescribed penalty for indecent exposure – of the female breasts, or of the male or female buttocks or genitals – is a fine of $100 to $500.

Last year, GoTopless protested at North Avenue Beach in the middle of the Air and Water Show. This year, their protest comes a week later.

The topless protests are organized by the Raelian Church, a UFO religion that teaches life on earth was scientifically developed by a species of extraterrestrials who were mistaken for gods. The Raelian Church also gained notoriety for founding the human cloning company Clonaid in 1997, and claiming to have cloned a human being in 2002.