On this day in history, October 21, 1931, the legendary gangster Al Capone was convicted of tax evasion and finally jailed.

While his list of crimes is long and brutal, it was the offense of tax evasion which finally brought down the infamous crime boss. Charged with 22 counts of the crime, though convicted on only 5 counts, he was sentenced to 11 years in a federal penitentiary. An appeal of his conviction ultimately failed.

Just 33 years old at the time of his conviction, he had been terrorizing Chicago and other parts of the U.S. for seven years of murder, racketeering and bootlegging during the Prohibition Era.

Despite his reputation as a gangster and as “Public Enemy No. 1,” Capone did not do well in prison. Initially incarcerated in Atlanta U.S. Penitentiary, his health quickly began to deteriorate, and he was subjected to relentless bullying by other inmates.

In August 1934, he was transferred to the now legendary Alcatraz Federal Penitentiary and is today regarded as its most famous inmate. His health continued to fail while imprisoned there. He suffered from neurosyphilis and became increasingly disorientated as his mental capacities failed.

Al Capone is widely believed to be the architect of the Saint Valentine’s Day Massacre in Lincoln Park, Chicago on Valentine’s Day of 1929. Seven men associated with the North Side Gang were executed at a local garage. While Al Capone could never be charged with the crime, his conviction of tax evasion was one of the few ways to bring this notorious gangster down.