Christo000, if by this you mean to go as at town hall "can I metal detect?", then no, I would disagree. But that type question can be taken as a form of "permission" (as if .... their "permission" were needed to do a particular activity). On the contrary: you wouldn't think you "need permission" to fly a frisbee, right? Or perhaps you meant to ask them if there's any prohibitions (or "any rules that address this", or something to that effect)? If so, then I'd tread very cautiously doing that. Because unfortunately, there's the risk of them morphing something ELSE to apply to your "pressing question", that they *think* applies. You know, the dreaded alterations or defacement clauses (even though you'll leave no trace). Or that they think you'll harm the earthworms, etc... Thus, no, I would not "go to town hall to ask someone". Instead, the OP ... if he's ultimately going to base it on actual rules anyhow, can look them up himself. Muni laws, codes, rules, etc.... are no "secret". They're available for public viewing SOMEWHERE
Or if you or someone is intent on talking to a live person, how about this: You ask them: "where is the publically available listing of laws, charter, codes, etc... of the city/county here". Then they'll give you a link. Or pull the binder from behind the desk. Or refer you to where it is, etc.... Presto. And if you see nothing there saying "no metal detectors", then there's your answer
Oh, and as far as the advice being so that you "don't have to look over your shoulder", well .. if someone's looked it up, and seen no prohibitions, they can print that out, and carry it with them for it a busy-body approaches.