Now I am not 100% sure on this one, why I am posting it. I was able to locate crashed up police cars in garages. I have not seen one since. It was in .52 that I came across 2 in one session. The server was in a locked up mode allowing me to run all around the map without realizing it wasn't performing correctly until I tried to jump.
This is where I figured out something was wrong, then I came across a police car in a garage. I tried to hit tab, but the server was messed up. Still was running but messed up.
A friend found the 2nd car all while speaking on TeamSpeak. We couldn't search the cars.
So I am not sure they are actually gone, or they are still spawning but not seen. Or it was simply a glitch and we shouldn't have seen the police cars. I have never seen one myself in 52 before this.