Re: The Riddle Gang
I think this make sense. Some sort of taboo. I might even argue that it's maintained by the Riddle Gang and maybe as more of them are dying the magic that keeps it is getting weaker.
I'm not sure if this will matter in game, but it's certainly an interesting thought.
It also makes me wonder if something similar protects the Dark Mark. Like why isn't the DMLE just running around demanding to see people's arms?