Marijuana is a controlled substance, and if a person is in possession of marijuana or marijuana-related paraphernalia they may be subject to arrest and charged with a crime. However, while this is the general rule, in some states marijuana has been decriminalized to varying degrees and medical use may even be permitted with a valid prescription from a doctor. Because laws surrounding the use of this drug differ from jurisdiction to jurisdiction, it is important to understand the rules that apply in your state or in any state that you plan to visit while in possession of marijuana. For more information about the laws associated with marijuana across various states, see the articles and answers to frequently asked questions in this section.