Colette Crutcher said she knows a little bit about being arrested for blocking the sidewalk, even if she wasn't doing that.

Crutcher, 52, said she was arrested decades ago on suspicion of blocking the sidewalk after peeking her head out of a cafe as police broke up a protest against former Secretary of State Henry Kissinger in front of a San Francisco hotel where he had been making an appearance.

And that prompted the self-described resident of the "People's Republic of Bernal Heights" to take a stand - well, a seat, actually - Saturday against San Francisco Mayor Gavin Newsom's proposed ban against sitting or lying on public sidewalks anywhere in the city.

"It sounds like it's something pretty antithetical to the spirit of San Francisco," said Crutcher, as she drew bright blue and green wave patterns on the sidewalk in front of the Bernal Heights Library. "I don't think there is any need for such a law. I think all it will do is encourage the police to stop people they don't like."

Crutcher was among about 10 people clustered in front of the library to protest Newsom's proposed sit/lie law, one of what organizers said were about 50 places across the city where residents took to the concrete as part of a "Sidewalks Are for People" campaign to thwart the legislation.

There was afternoon tea in Cole Valley, a neighborhood party north of the Panhandle Park and barbecues at various spots.

People drew with chalk on the sidewalks, did yoga and grumbled that San Francisco was slipping toward a police state.

"It seems un-American to me, to go after the most vulnerable people in our society," said Allen Trachtenberg, 82, who was handing out flyers that read: "There are already enforceable laws against aggressive behavior. Criminalizing sitting on the sidewalk won't solve anything - it will just turn more of us into criminals."