The question of legality is a tricky one. The California statute echoes the federal one, a radio receiver is legal except in the furtherance of a crime. Now here's the tricky part, LA County enacted a prohibition ordinance back in the 40s that was amended in 1988 but I can't find any current information on it, you may want to invest some more time than I had. Then there are local codes and ordinances that make it like tap dancing in a minefield while juggling hand grenades.
The laws vary widely across the country and New York has the worst possible so the best advice I can give anyone especially the traveler is when in doubt don't. Always make sure what the laws are in the areas you monitor in and travel through to get there, in some instances mere possession of a mobile or portable receiver, even locked in the trunk is illegal.
"Even if you are a ham radio op, there are some states where you may run into problems if they pull you over and find that you are listening to their frequency."
Here it is explained, just having a public service frequency programmed or the VFO sitting on one can get you in trouble and having a ham license won't get you out of it. That it will is a common misconception, the fact of the matter is Amateur transceivers CAPABLE (and all VHF/UHF units are) of receiving PS frequencies are exempt but actual USE is another matter entirely! In other words if it is used for scanner monitoring it is considered as a scanner under the law. Don't let yourself be confused, listening outside the Amateur bands is perfectly legal as long as it's not to the cops, they hate us listening to them to begin with and would wring our little necks for us if they can.
Oh I expect the usual responses so I leave you guys to ponder this question. Do you REALLY like those unpleasant surprises when you get lit up for some minor violation and one thing leads to another?
