A quick Google reveals..
It seems this insane tableau is the brainchild of a man who was denied permission to install a pond in his garden by the local council. So, obviously, he went out and put a guy in the ready position on the roof of a foreign police car. Way to lash out friend!
The website is no longer active however it is an imitation of an LAPD squad car. Maybe the number 54 is a reference to the US tv series "car 54 where are you" or maybe to the Blues Brothers film with the pork pie hat, who knows. This was way back in 2000/2001!
The other car is a well known type of British Sports car, known as an MG often driven by young ladies and gents having been given the car for an 18th birthday by well off parents, or by hairdressers.
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