Rule in Albion is devolved to local authorities. Essentially, whoever owns the nearest manor house/ fortress/ folly is responsible for the security of the surrounding area (and those who live there).
Small towns make do with a magistrate to settle differences, and often rely on ‘the mob’ to right particularly pressing wrongs.
Crime at the level of peasant is practically nonexistent to the ruling classes.
Larger towns (or areas with a particularly benign or wealthy/ paranoid Lord) might have a detachment of soldiers garrisoned there, or a semi-professional watch. Either way, a constable will often be a visible presence.
The constable will more-often-than-not be pressed into tax-collection and heavy-handed enforcement; rare is the constable who’s driven by a sense of morality.
Of course this is make-believe, so the constable, and the Watch, has duties beyond the historical model. Monsters prowl the wilderness, interfere with trade, attack dignitaries etc, and it often falls to the constable to intervene – or at least make someone else do it.
Assume then that the constable (sheriff?) fancies her/ himself as a bit of a dictator, and that the calibre of those roped (blackmailed?) into working under them is only marginally above that of a common thug. Obviously this isn’t always true, but where’s the fun in having respectable lawmakers?
They’ll need leather armour (maybe something heavier if you feel it’s appropriate), and will almost certainly have a rapier. The more loathsome specimens make do with a cudgel. Save as Fighter Level 1. The Watch would be basic 0 Level types. No treasure should be forthcoming.
The constable (and her/ his band of thugs) would make a cheerful random encounter, and would almost certainly turn up if a group of suspicious-looking player characters cause a ruckus at the local brothel/ start shooting fireballs in the temple.