History has valuable lessons to teach policy makers but it reveals its lessons only grudgingly.
Close analyses of the facts and their relevance is required lest policy makers fall victim to the persuasive power of false analogies and are misled into imprudent judgments. Just such a danger is posed by those who casually invoke the ''lessons of Prohibition'' to argue for the legalization of drugs.
What everyone ''knows'' about Prohibition is that it was a failure. It did not eliminate drinking; it did create a black market. That in turn spawned criminal syndicates and random violence. Corruption and widespread disrespect for law were incubated and, most tellingly, Prohibition was repealed only 14 years after it was enshrined in the Constitution.The lesson drawn by commentators is that it is fruitless to allow moralists to use criminal law to control intoxicating substances. Many now say it is equally unwise to rely on the law to solve the nation's drug problem.
But the conventional view of Prohibition is not supported by the facts.
Second, alcohol consumption declined dramatically during Prohibition. Cirrhosis death rates for men were 29.5 per 100,000 in 1911 and 10.7 in 1929. Admissions to state mental hospitals for alcoholic psychosis declined from 10.1 per 100,000 in 1919 to 4.7 in 1928.
Arrests for public drunkennness and disorderly conduct declined 50 percent between 1916 and 1922. For the population as a whole, the best estimates are that consumption of alcohol declined by 30 percent to 50 percent.https://www.nytimes.com/1989/10/16/opinion/actually-prohibition-was-a-success.html