The Marijuana Tax Act of 1937 was the first federal U.S. law to criminalize marijuana nationwide. The Act imposed an excise tax on the sale, possession or transfer of all hemp products, effectively criminalizing all but industrial uses of the plant.
Fifty-eight year-old farmer Samuel Caldwell was the first person prosecuted under the Act. He was arrested for selling marijuana on October 2, 1937, just one day after the Act’s passage. Caldwell was sentenced to four years of hard labor.
Industrial hemp continued to be grown in the United States throughout World War II, when its domestic cultivation was encouraged after the Philippines—a major source of imported hemp fiber—fell to Japanese forces. The last U.S. hemp fields were planted in 1957 in Wisconsin.