Even within the state, there are varying levels of enforcement for mechanical violations. I've been a cop for about 30 years. I have never ever been trained with a window tint meter...I leave that stuff to the CHP or traffic cops in my dept. I, personally, don't need to waste my time looking for a funky brake light or overtinted window UNLESS I NEED AN EXCUSE TO STOP A CAR. If I think it is a gang member or something, a mechanical violation is all I need to justify lighting him up. Failing the attitude test is an instant vehicle equipment safety check, however.
Anyway. I just came back from a trip to LA/Hollywood. It is incredible the amount of potential mechanical violations down there. Tinted windows abound, as do modified (and exceeding the db limits) exhausts and non-spec headlights. Every other car seemed to be modified, loud and speeding.
However, in the small towns not included within the LAPD jurisdiction apparently they pounce readily upon mechanical violations. Tint meters and db level measurement devices in hand, the basic patrol cops do double duty as vehicle inspectors so I guess alot of the cars I see cruising Sunset Blvd. avoid the small towns.
On the overzealous CHP types...alot of CHP zones are training areas for CHP officers who have just hit the street. Like ALL new police officers, new CHP members are often tasked with practicing all facets of enforcement so those areas are more prone to subject drivers to more detailed inspection of their cars.
FYI, under current protocol, we are required to tell a person why we stop them, and to ask them if there was a reason why they did what they did. In training, the recruits have to
precisely recite a script that goes something like this, "Hello. My name is deputy Fife of the Mayberry Sheriff's Department and the reason I stopped you is because I saw you fail to stop at the stopsign back there on Mayberry and Main streets. Is there any reason why you didn't stop there?"
In my day, it was, "Where's the fire? License, registration and proof of insurance...keep your hands where I can see them." Times are changing.
FYI, to this day, I have never issued a citation for tinted windows.