The law legalizing marijuana use is federal, but each Canadian province and state can add laws on top of that.

For example, the province of Alberta has some of the most liberal laws on marijuana use, but Calgary -- the biggest city in Alberta -- has banned the use of recreational pot in public. Violating the law could mean a $100 ticket. Recreational marijuana use is legal in private places, but landlord and tenant agreements are allowed to forbid cannabis use, the city says.