Marijuana is only legal in the state of Arizona for medical purposes; in order use marijuana, you have to have a valid ARIZONA medical marijuana card and be obeying the law. Thus, if you’re card is not officially you registered, you are not permitted to use marijuana. Even if you do have a card, there are still some restrictions. For instance, you cannot use medical marijuana on a college campus, nor can you use marijuana while possessing a firearm. Be careful–even the smell is enough for probable cause for you or your property to be searched.