Prohibition refers broadly to the legal ban on the manufacture, sale, transportation, importation, and exportation of alcoholic beverages. In American usage, the term most often designates the national period from 1920 to 1933, during which the Eighteenth Amendment to the U.S. Constitution and the Volstead Act prohibited the production and sale of intoxicating liquors. Similar policies were enacted in other countries during the late nineteenth and early twentieth centuries, including Canada, Finland, Iceland, Norway, and Russia. Prohibition movements arose from a confluence of temperance advocacy, Protestant moral reform, and Progressive-era reform politics, and their legacy continues to inform debates over drug policy, regulatory governance, and the limits of legal enforcement.

The temperance movement that preceded American national Prohibition dated to the early nineteenth century and drew support from Protestant churches, women's suffrage organizations, and labor reformers. Statewide and local prohibition laws were in effect in several U.S. states before the Eighteenth Amendment took effect on January 17, 1920. The Volstead Act (formally the National Prohibition Act, enacted October 28, 1919) defined the enforcement mechanisms. Prohibition was repealed by the Twenty-First Amendment on December 5, 1933, making it the only constitutional amendment to repeal another.

The Prohibition era is associated with a significant expansion of organized crime, as criminal networks supplied illegal alcohol through speakeasies and bootlegging operations. Federal and state enforcement was inconsistent, and violations were widespread. Consumption patterns during the period remain debated: some evidence suggests alcohol consumption fell sharply early in the period, while other indicators point to partial recovery over time. The economic effects included the loss of tax revenue from the liquor industry, the growth of illicit markets, and significant costs of enforcement.

Historians, economists, and policy analysts have offered varying assessments of Prohibition's causes, effects, and lessons. Whether Prohibition succeeded or failed—and by what criteria—is a subject of ongoing scholarly discussion. See Prohibition – Debate for competing interpretations.

There is broad scholarly consensus that national Prohibition reduced overall alcohol consumption in the United States compared to pre-Prohibition levels, at least during the early years of enforcement. Consensus is substantially weaker on the magnitude of that reduction, the degree to which consumption recovered before repeal, the net public health impact, and the causal relationship between Prohibition and the expansion of organized crime. See Prohibition – Social Science Consensus for a summary of the research literature.

• Prohibition as failed social engineering — Holds that national Prohibition was a coercive overreach that failed on its own terms, produced substantial harms (organized crime, corruption, mass legal contempt), and demonstrated the limits of using law to regulate private behavior. See Prohibition – Failed Policy Viewpoint.

• Prohibition as partial public health success — Argues that Prohibition measurably reduced alcohol-related disease, domestic violence, and workplace accidents, and that its failure narrative overstates the influence of enforcement problems relative to genuine health gains. See Prohibition – Public Health Viewpoint.

• Prohibition as moral and religious reform — Frames Prohibition as an expression of legitimate democratic and religious opposition to alcohol as a social harm, distinct from questions of enforcement efficacy. See Prohibition – Temperance Viewpoint.

• Prohibition as Progressive-era governance — Situates Prohibition within the broader Progressive movement's project of using federal power to address social problems, analyzing it as a case study in regulatory ambition. See Prohibition – Progressive Reform Viewpoint.

• Prohibition as a template for drug policy — Draws analogies between alcohol Prohibition and twentieth- and twenty-first-century drug prohibition, arguing the two share structural features with common policy implications. See Prohibition – Drug Policy Analogy Viewpoint.

• Prohibition as government overreach — Argues that Prohibition was objectionable on individual liberty grounds independent of its practical outcomes, treating the regulation of private consumption as beyond the legitimate scope of law. See Prohibition – Individual Liberty Viewpoint.

• Prohibition – History
• Prohibition – Debate
• Prohibition – Social Science Consensus
• Volstead Act
• Eighteenth Amendment
• Twenty-First Amendment
• Temperance Movement
• Organized Crime
• Drug Policy
• Progressive Era

~~FOOTNOTES~~

1. Okrent, Daniel. Last Call: The Rise and Fall of Prohibition. New York: Scribner, 2010.
2. Blocker, Jack S. “Did Prohibition Really Work? Alcohol Prohibition as a Public Health Innovation.” American Journal of Public Health 96, no. 2 (2006): 233–243.
3. Thornton, Mark. The Economics of Prohibition. Salt Lake City: University of Utah Press, 1991.
4. Kyvig, David E. Repealing National Prohibition. Kent, OH: Kent State University Press, 2000.
5. Miron, Jeffrey A., and Jeffrey Zwiebel. “Alcohol Consumption During Prohibition.” American Economic Review 81, no. 2 (1991): 242–247.
6. Lerner, Michael A. Dry Manhattan: Prohibition in New York City. Cambridge, MA: Harvard University Press, 2007.