The repeal of Mullan-Gage did not legalize alcoholic beverages in New York, for the Volstead Act remained in force. Repeal only meant that New York police and New York courts, no longer bound by the state to enforce federal antibooze laws, could hand full responsibility over to Washington–“where,” said [New York governor Al] Smith, “it rightfully belongs.” If speakeasies kept the racket down and didn’t disrupt the peace of the neighborhood, city police left them alone. A sign went up over the bar at Leon & Eddie’s, on West Fifty-second Street: “The bar closes at three o’clock. Please help us obey the law.”

Enforcement did take place in Detroit; it just didn’t have anything to do with drinking. A succession of mayors and police chiefs would occasionally crack down on places that were disorderly, or fostered criminal activity, or belonged to an ugly category known as “school pigs,” sleazy operations set up near high schools. But any establishment that obeyed the rest of the criminal code–all the laws that had nothing to do with Prohibition–was left alone.

These two passages are from Last Call: The Rise and Fall of Prohibition by Daniel Okrent. They remind me, especially the first one, of the distinction that Donald Boudreaux often makes, drawing on Friedrich Hayek, between law and legislation.