On July 12, 17 people were arrested during a scuffle between protesters and police at Dowtown L.A.'s ArtWalk. The protest spurred from a recent police crackdown on chalking by members of the Occupy L.A. movement outside the offices of the Central City Association at Hope St. and Wilshire Blvd.

At this week's meeting of L.A.'s Police Commission, a core group of Occupiers showed up to lodge complaints against the crackdown — what they described as police acting aggressively towards an innocuous and widespread activity, writing with sidewalk chalk. Several speakers pointed out that kids in the city often chalk sidewalks, and adults, too.

The first big question is if, in fact, chalking is illegal. UCLA Law Professor Eugene Volokh, who specializes in the First Amendment, says that according to California law, it is.

"California law says that any person who malisciously, with respect to any real or personal property not his or her own, defaces it with inscribed material, is guilty of a crime," Volokh said. "It's clear, from past cases, that includes inscribed material that's relatively easy to wash off."

Federal judges have consistently found that chalking bans don't violate the Constitution's protections on freedom of speech. That's "because it leaves plenty of alternate channels for expressing yourself," Volokh says, while "protecting the property rights of the government and preventing visual blight." 

Occupiers, however, have argued that the LAPD has not enforced the city's vandalism laws equally, allowing kids and others to draw on sidewalks unperturbed.  

James Hill, who said his friend was arrested at ArtWalk, told the Police Commission he recently passed Pepsi advertisements written in chalk on the Venice Boardwalk. "I don't think anyone's arresting people from Pepsi Co," Hill said. "This is one of the most egregious abuses of police power, is to selectively enforce a law. Especially when the apparent intention of selectively enforcing that law is to supress people's first amendment rights."

Volokh says that's a good point — chalking bans are constitutional specifically because they're content neutral. "This having been said," Volokh says, "I suspect it's not that there's a solid police department policy of enforcing the law only in a political context, it's just that they never get called with regard to somebody playing hopscotch on the sidewalk."

Moreover, Volokh says, the city can allow chalking at certain times and places — say, hypothetically, chalking day at the Venice Boardwalk — without that lenience constituting unequal enforcement. The government, he says, has rights that are similar to those of private property owners, "and one of the rights is to take property that is otherwise jealously guarded for their own purposes and turn it over to other people for some purpose. So the fact that they open it up every so often, a limited chunk of sidewalk for schoolkids to do something and then they wash it all off some days later, doesn't require them to them open up all the sidewalks indefinitely to everybody."

So long as there's no stated or effective city policy saying vandalism laws will only be enforced when it comes to political scribbles, Volokh says, the city is constitutionally in the right.