And VERY often the cop you ask doesn't even know the law! I have asked cops things or been pulled over for things only to find out they were wrong when I went to the vehicle code book.
So just asking a cop doesn't mean much really. They aren't perfect. And among the urban hot rod myths, they have been rapid for years. Here in California at least "The windshield has to be 12" (make up a number) high" Wrong, the tail lamps have to be a certain diameter, wrong, it goes on and on. How's this for an interesting one on hot rods here in California, you don't need headlamps mounted on the car during daylight, but you do need wipers at all time, now that is the law.