Pinball was banned from the early 1940s to the mid-1970s in most of America's big cities, including New York, Los Angeles and Chicago, where the game was born and where virtually all of its manufacturers have historically been located. The stated reason for the bans: Pinball was a game of chance, not skill, and so it was a form of gambling. To be fair, pinball really did involve a lot less skill in the early years of the game, largely because the flipper wasn't invented until 1947, five years after most of the bans were implemented. Up until then, players would bump and tilt the machines in order to sway the ball's gravity. Many lawmakers also believed pinball to be a mafia-run racket and a time- and dime-waster for impressionable youth. (The machines robbed the "pockets of schoolchildren in the form of nickels and dimes given them as lunch money," New York Mayor Fiorello La Guardia wrote in a Supreme Court affidavit.)
In New York, the pinball ban was executed in a particularly dramatic fashion. Just weeks after Pearl Harbor was attacked, Mayor Fiorello La Guardia issued an ultimatum to the city's police force stating that their top priority would be to round up pinball machines and arrest their owners. La Guardia proceeded to spearhead massive Prohibition-style raids in which thousands of machines were rounded up in a matter of days, before being dramatically smashed with sledgehammers by the mayor and police commissioner. The machines were then dumped into the city's rivers.
Like New York, Los Angeles banned pinball machines in 1939. The ban was overturned by the Supreme Court of California in 1974 and New York in 1976 because (1) if pinball machines were games of chance, the ordinance was preempted by state law governing games of chance in general, and (2) if they were games of skill, the ordinance was unconstitutional as a denial of the equal protection of the law.
The topmost photo is of George Schmabel who in this pic is trying to prove to the courts that Pinball is not a game of chance but one of skill. The second photo is Police Commisoner William O'Brien taking a sledgehammer to a machine in March 1949. It has been reported that the police destroyed 2,259 of the machines that night.
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