Prohibition
The Prohibition Act has done nothing but cause more drinking and crime, despite what it was intended to do. The act made any drink containing more than 0.5 percent alcohol illegal. Instead of making alcohol harder to get it actually got easier, you could just walk down the street and find someone selling some form of alcohol. Organized crime went way up and has made finding and buying alcohol even easier then it has ever been before. People are drunk all the time and some are even dieing from some form of poisoning from it.
There is also a lack of enforcement on these new laws. And if you have the money you can bribe any authority, mostly federal agents and people of high political status. As a result of this crime has gone up to nearly twice what it was before Prohibition. In the large cities crimes such as homicide has gone up nearly 78% from what it was before. Only minor crimes have gone down such as swearing, mischief, and vagrancy. Even though crimes in general after Prohibition went into effect went down for a short time but in general crimes skyrocketed.
Organized gangs also have come into the picture. With names such as Johnny Torrio, "Bugs Moran", the Gennas, and the O'Banions. The most powerful of these though, was Al Capone who operated out of Chicago. Capone did just about any thing to stay in business, Even having one of his gunmen kill off a rival gang. In this case it was the O'Banions, led by Bugs Moran, so on Valentines Day 1929 he killed of pretty much all of the O'Banions.
So basically in the end Prohibition was a complete waste of time because it was later repealed. Crime and drinking increased dramatically. A lot of the time the authorities where bribed so even if they where around it didn't matter much any way.