Iowa, Nevada, Oregon, Washington and Arkansas all passed laws regulating marijuana in 1923, joining Massachusetts (1911), Maine (1914), Wyoming (1915) and Texas (1919). Nebraska and Louisiana followed in 1927 and Colorado in 1929. Outright prohibitions spread through the 1920s, the decade of national alcohol Prohibition, during which cannabis was seen as a cheaper alternative to drink.[1]
Listed for context. No score change is recorded for United States here.
References
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