I'm all for having functional police forces. I'd prefer they be privatized, but in the absence of that, I'll gladly have a police force tasked with apprehending people who violate my property rights and those of others. On the flip side of that, those police forces must be held to the same liability standard as private persons, as they occupy no greater sphere of rights an a private person. If you fuck up as a cop and arrest someone who is latter released without charge, you should be liable to arrest for false imprisonment. That's on top of the civil liability, which should come from somewhere other than the city coffers outside of police funding.