That to me doesn't sound so easy, but not so hard either, I'm trying to imagine it and we could get some coordinates for the police/prisoners etc. and could spawn some police cars but I don't know about dropping prisoners off.
For the fights inside the prison, yeah, that's possible. Also "Hidden weapons" around the prison would be possible, again, we'd need coordinates.
If you were thinking about a riot somewhere in amongst this then I think that would also be possible by setting the peds to hate eachother (Guards v prisoners).
But with the stars, do you mean if you get a 3 star, then you get taken to the jail (Most likely teleported), have your player model changed to some prison ped and then try to break out? If so, then I can see that as being possible. Almost like a mini-game I suppose.
HuN may or may not look into this, I can't speak for him, but he does this kind of thing very well and I believe he has even more ideas to come. He might even decide to take this up, who knows.
I may look into it myself when I have more time, I'm currently blastin' some fools on Assassin's Creed 3
Good luck with this.
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