Legal Question in Technology Law in California

First, I doubt this matter is suitable for police attention. However, if what is being displayed to the public amounts to a threat to commit a crime, my answer would be different. As a general matter, I'm inclined to think your local police will tell the individual that it's outside their duties and that "It's a civil matter" which is kind of a generalized police way of telling complaining citizens that they're too busy trying to catch muderers, burglars, robbers and so forth. Your "fan" might, however, decide to talk to a lawyer instead of the cops if he gets the notion that he is being defamed.