You as a citizen pay taxes and in return a significant portion of that budget is spent on the public services of the police, and in greater danger, the military (irl, it's questionable how much you should be spending here and other politics but

These people are expected to enforce the order of their realm, and claims should have a warning system that tells the realm owner that they have obtained scents or a criminal act transpired to investigate. To make it easier, let's just say it magicked its way or got to them by carrier pidgeon, either way, this gives people a sense of security if the realm owner can protect the realm for real.
This could be addressed ingame by players themselves managing this kinda thing but a more official, secure, and automated system for taxes seems ideal.