Great question! (and of course I have a vested interest in this particular one :)
I'd be in favor of John's historical lock suggestion. I think it's important to keep this question because:
- the currently marked answer does manage to avoid talking about legal specifics
- it is inherently answerable
- due to mystique and misinformation many other random visitors are likely to have the same (or similar) questions (so it is a useful reference question)
With regards to the Legalities of martial arts off topic option I think it is useful to break it down a bit:
- we (I) are not lawyers so are not necessarily qualified to talk about legal specifics
- laws are different everywhere, this can lead to very localized answers
- laws are interpreted, which can lead to arguments
- like medicine, law is a privileged and specialist topic
so while we should try and avoid questions about legal specifics, I feel there is no reason why we can't still ask questions about legalities in general, which is what this question does.
Of course the simple answer for the linked question would have been "Well, duh, yes...", but I think it's important that we have the flexibility to expound on these where necessary, even if we come at it from a philosophical view point.