That may be tricky and interesting.
I have a suggestion if that's acceptable. Everyone who read forums, now know that, everone alse don't, they may hear it somewhere but there will still be really many people who won't realise.
The idea is when you are about to reach a forbidden place, something has to warn a player that he is about to enter a place some NPCs will hate him for. Without clicking anything at all (1) A guard who will shout uppon seeing the player character: "You will go further on my body, by Yliakum law you are not allowed to enter burrial well (or some other publicly forbidden location)"
If there is noone around a place you shouldn't enter then how can anyone at all know you entered it... Everyone know your face at once and refuse to talk/trade/train or what else wit your character.
(1) because if you put a waysign, which will show these weird symbols nooe can understand, and there won't be a label above it (I hate current blood-red signs btw), noone is going to think there is a warning on it. Even if there is a burrial well sign, most of the people won't know it is a sin to enter one, because something what yliakeans are learning since childhood, players dont know at all about. If no-one tell them before, they won't know, for instance noone is going to a library to read all the laws, because they are supposed to be a common knowledge, players learn them along ther journey through Yliakum.
If a player character broke the law and the guards somehow know about it, then they have to tell him whats wrong and he needs a chance to repay for his sins. Because maybe he didn't know he did omething wrong at all, but now he knows and won't repeat if smart.
