I was a Policeman in Essex; one early turn we got a call from an old boy and his Missus that there was a car in their front garden. We went round and it had crashed off the road, crossed their drive, and come to rest right up against the front door.
We checked the legal position with my Sergeant; Essex Police were skint, so we wouldn’t tow it; the Council would charge the elderly couple. The car had drugs paraphernalia inside (no drugs though) and no current keeper. Plainly some scrote had bought it, crashed it (probably driving on drink/drugs) and scarpered.
We told the elderly couple not to worry. I returned off duty at 2pm when we finished work, driving in my elderly Land Rover with my son (aged 7!) then we towed it off their lawn and left it on the public highway. Then we reported it to the Council. Jobs a good’un.
A nice letter of thanks resulted, which both of who attended the original call denied knowing anything about and was told (with a wink) by the Chief Inspector that it couldn’t have been us as it would be an abuse of procedure, so it obviously never happened!
I’m not sure we’d get away with it these days, sadly, the world is a less ‘output focused’ place these days, it would probably offend somebody and result in a chest beating admission of guilt by the Police, and sackings.