Drug possession, manufacturing, and distribution are illegal under federal and state law. Every state creates its own drug laws, as well as the punishments that a conviction carries. Like other states, Montana lawmakers break all controlled substances down into several schedules. Schedule I drugs are those that have no current medical use and present a very high risk of addiction. On the other end of the spectrum, Schedule V substances have a variety of medical uses and, while still potentially dangerous, pose much lower risks.