You've invited a group of friends over for a party. Someone is smoking a joint. It's late. It's loud. A neighbor calls the cops to complain about the noise. When the police arrive, they smell marijuana and make an arrest. Tenants are responsible for what goes on in their homes. You may end up facing criminal charges and also be subject to eviction. Prohibit anyone in your home from engaging in any kind of illegal activity. Or you may find yourself living someplace else.