This is kind of a companion question to this one (How to reconcile a feudal system with a congressional/parliamentary democracy...?), so if you are looking for some extra context, you can read this question first.
I realize the anachronistic nature of this concept, but that's kind of the idea. I am just mostly interested in seeing how to combine conventions and workings of modern law enforcement, within reason, with a medieval/Middle Ages setting and the challenges that presents.
I know, for example, that knights were supposed to hold the peace over land that they were assigned, and that in some countries this was such a task for a single person (or a small group of people) that the ancient precursors of our idea of "police" were basically armed volunteers, groups that were supposed to eventually go away and never did. And in other parts of Europe, local lords appointed people under a constable to handle the law for them, etc. It's traditions like that which I want combined with present-day police forces, insomuch that that is possible.
If I need to refine the topic, let me know.