News Corp has an interesting article on police co-operation on TV shows, providing uniforms and assistance in production.
As I recall, Blue Heelers had a resident ex-cop as part of its writing team and as a result the co-operation of Victoria Police.
As this article indicates, Victoria Police has a Film and Television Office, staffed by a combination of Victoria Police members and public servants.
“We’ve got a basic supply of uniforms, from the ‘80s, ‘90s and the new uniform,” said Sergeant David Spencer from Victoria Police.
“We provide the stock uniform with our integrated operational equipment vest (IOEV) but without the kevlar in it, and the uniforms themselves don’t have any Victoria Police logos on them at all, but a lot of the companies make up their own police badges.”
Some shows, such as Rush, prefer to feature a fictional State Police, partly so as to create storylines that don’t require sign-off, or to not tie themselves to a particular location.