(Prohibition and Homicide Rates) "The data are quite consistent with the view that Prohibition at the state level inhibited alcohol consumption, and an attempt to explain correlated residuals by including omitted variables revealed that enforcement of Prohibitionist legislation had a significant inhibiting effect as well. Moreover, both hypotheses about the effects of alcohol and Prohibition are supported by the analysis.
(Illicit Substance Use by 'Lifetime' Alcohol Users in the US) "Lifetime alcohol users aged 21 or older had a significantly higher rate of past year illicit drug use (13.7 percent) compared with lifetime nondrinkers (2.7 percent). In addition, lifetime alcohol users had significantly higher rates of past year use across all illicit drug categories, with the exception of inhalants (Table 1). Nonmedical use of pain relievers was the illicit drug used most often by lifetime nondrinkers, whereas lifetime alcohol users reported using marijuana most frequently."
('Lifetime' Alcohol Users and Other Drug Use) "In 2002 and 2003, an estimated 88.2 percent of persons aged 21 or older (175.6 million) were lifetime alcohol users, whereas an estimated 11.8 percent (23.5 million) were lifetime nondrinkers. Over half of lifetime alcohol users (52.7 percent) had used one or more illicit drugs at some time in their life, compared to 8.0 percent of lifetime nondrinkers.