I have bad news. California's vandalism law prohibits maliciously:
- defacing property with graffiti
- defacing property with inscribed material
- damaging property
- destroying property
Chalking the sidewalk probably doesn't sound very malicious, but maliciousness includes “an intent to do a wrongful act, established either by proof or presumption of law.” So the questions is whether you intended to do a wrongful act -- meaning that you intended to do the act, which happens to be wrongful, not that you intended to act wrongfully. So unless you drew on the sidewalk accidentally, the malicious-intent requirement isn't going to help you.
So then you have to ask if your conduct is described by the statute. In Mackinney v. Nielsen, the Ninth Circuit said that sidewalk chalking did not violate the law, but California has since amended the law to add the "deface with graffiti" language. I haven't seen any chalk cases since then, but another case, In re Nicholas Y., from the Second District, dealt with someone who used a marker on a window. He argued that it could be easily erased, but the court said it was still vandalism because:
- it "mars the surface with graffiti which must be removed in order to restore the original condition"
- the definition of "deface" "does not incorporate an element of permanence"
- "marring of the surface is no less a defacement because it is more easily removed."
Given that language, I'd argue that the vandalism statute includes sidewalk chalking.
But one important element here is that most sidewalks are owned or controlled by the government, so any effort to restrict "expressive conduct such as writing with chalk" (Guilliford v. Pierce County) expressive activity" there must comply with the First Amendment.
The government has varying degrees of latitude on the restrictions it can impose, depending on the character of the space involved. So in a courtroom, whose function is incompatible with free-wheeling public debate, a judge can set quite a few rules about how people may speak. But sidewalks are considered a "public forum," where the government's ability to regulate speech is a lot more limited.
So how does the First Amendment apply?
There's a D.C. Circuit case (Mahoney v. Doe) dealing with abortion protesters who wanted to use chalk on the streets and sidewalks outside the White House. Police told them they would be arrested for violating D.C.'s defacement statute, so they brought a First Amendment challenge. The court upheld the law, saying that it satisfied all three prongs of the public-forum test:
- The law must be content neutral, meaning that it prohibits conduct without reference to what is being said. The Court said the defacement statute was content neutral because people could be prosecuted regardless of what they wrote or drew.
- The law must be narrowly tailored, meaning that it serves a significant governmental interest and does not restrict more speech than is necessary to achieve that goal. The Court said the defacement statute was narrowly tailored because it served the government's interest in maintaining the aesthetic appeal of the area in front of the White House and didn't restrict any speech that does not deface public property.
- The law must leave open ample alternatives for communication, meaning that even if you can't express yourself in the way restricted, you still have meaningful opportunities to express yourself. The Court said the defacement statute law allowed adequate alternatives for communication because the group could still congregate, march, speak, hold signs, and hand out leaflets.
There's an interesting wrinkle there in terms of whether the interest in aesthetics is heightened because we're talking about the White House, but generally speaking, aesthetic concerns can still justify speech restrictions.
So the bad news is that unchaining your inner six-year-old may subject you to criminal liability. That leaves the question of whether you want to unleash your inner teenager and do it anyway. This could help put you in a frame of mind for making the decision.