A visitor smokes a joint during the first Cannabis Cup where self-cultivation and the quality of the herb are encouraged, in Tlajomulco de Zuniga, Jalisco State, Mexico, on March 18, 2018. (Photo by ULISES RUIZ / AFP) (Photo by ULISES RUIZ/AFP via Getty Images) AFP via Getty Images For more than a decade, the American cannabis industry has occupied a strange legal purgatory: legal in some form in more than half the states yet still prohibited at the federal level.