Well, as the subject says I think there should be certain weapons/items/magic that are illegal in certain cities or everywhere.
For magic, since some people don\'t trust it, it could be banned in some cities. Also certain spells such as invisibility could be banned. If they were caught using/casting the spell they would be fined/thrown in jail/killed depending on how strong hte spell is.
Some items should also be illegal such as a certain type of poison along with many other things that could only be bought through black market or trade.
EDIT: meh