In the vanilla game/Classic Elite the police are paid for by GalCop, the United Nations equivalent, which presumably used to police pretty much everything in the Golden Age.
There are more police and fewer pirates in the safer systems.
The consensus on these boards has been that the wealthier systems pay in more money to GalCop and thus get better police coverage in their systems. Hence they are safer (Commander McLane and others).
There are several points about all this.
1)
Anarchies. Where does the money for police in anarchies come from? And where does the money for the Main Orbital Stations in the anarchies come from?
The anarchies contain no governments capable of paying in to any of this. Just individual billionaires,
etc.
If we can presume that the anarchies only became such after the decline and fall of GalCop, then the money would have been there previously to put them in orbit.
But that does not account for the funding of their current police forces. Either the fledgling coverage is paid for by revenues from the Main Orbital Station - or from grabbing some from wealthier systems. Or both.
2)
Commies & Dictatorships. OXP Commies and OXP Dictatorships have their own police.
For the Commies it makes sense. The
Comoonin has organised centralised police for the systems, duplicating GalCop's efforts elsewhere. But the Dictatorships do not seem to have equivalently centralised co-ordination.
First, they are split between the juntas and the Imperialists, weakening their clout. But there is no evidence that either are centralised, apart from their ships and stations. If the Imperialists were centralised into the one big Empire, one would assume that we would all know about it. But perhaps they were centralised back in the Golden Age.
3)
Other systems.
Corporates want to protect trade, so they presumably pay extra to GalCop to ensure better police coverage. They
could have their own forces, as suggested above, but my understanding is that they pretty much control GalCop (except perhaps in G4). So would they bother? If the main reasons for police are suppressing piracy and clobbering Thargoids, then GalCop can do it for them.
Democracies, well! Now that we have dear old Donald showing us all how to do his own thing, perhaps our Democracies would vary massively!
Confederacies and
Multi-Govs I see as mixes of the more flavoursome systems. And thus may well contain the odd SothisTC/Astrogulag
etc. Whilst the poor
Feudals can neither afford their own police nor contribute significantly to GalCop to provide better police coverage.