History and Uses of Marijuana Whether you call it Hemp, Mary Jane, Pot, Weed; it doesn't matter. It is still Cannabis Sativa, or cannabis for short. And it is still illegal. The use of marijuana as an intoxicant in the United States became a problem of public concern in the 1930s. Regulatory laws were passed in 1937, and criminal penalties were instituted for possession and sale of the drug. "Marijuana" refers to the dried leaves and flowers of the cannabis plant, which contains the non-narcotic chemical THC at various potencies. It is smoked or eaten to produce the fee