On July 12th, participants in OccupyLA met to raise awareness for unlawful arrests of activists that had been targeting a lobby group with a stranglehold on power over local and state politics. The activists handed out chalk and shared the story of unlawful arrests and police repression.
It seems that in Los Angeles, California, it isn't chalking that's illegal. It's the message. Participants of Chalk Walk Respond to Mayor’s Statement & Selective Enforcement here. You can't arrest an idea.