On the night of April 27, the Big Guy himself went out to spread fear. He tailed a Lincoln carrying Klondike’s brother Myles and some of his henchmen. On the way to the Pony Inn O’Donnell had picked up twenty-five-year-old Bill McSwiggin. Bill lived at home with his parents. His father was a Chicago cop, and he himself was an assistant state’s attorney, a sharp young prosecutor who had won seven of the eleven first-degree murder convictions in the city the previous year. He’d once unsuccessfully prosecuted Myles O’Donnell for murder.

As the O’Donnell group alighted in front of the tavern, Capone’s car approached from the east. A burst of machine-gun fire ripped into three of the men. Myles and his driver escaped unharmed. They wrestled the bloody bodies of two of their companions, including McSwiggin, into the car and dumped them in another suburb.

McSwiggin’s killing shocked Chicago and the nation. Gangsters killing gangsters was one thing. To gun down a prosecutor went beyond the pale. In a spasm of indignation the police raided speakeasies and gambling parlors around the city. McSwiggin’s boss, Robert E. Crowe, who had never proved himself capable of solving a single gangland murder, swore, “We are going to get to the bottom of this.”

But as the shock subsided, the city faced troubling questions. Why was an assistant state’s attorney consorting with the very lawbreakers he was sworn to prosecute? How closely was McSwiggin linked to the underworld forces that seemed to be gaining control of the entire city? Why were gangsters allowed to kill with impunity? Cynicism began to replace sympathy.

Five grand juries failed to indict anyone for the murders. Capone was questioned and released. He reportedly handed McSwiggin’s father an automatic and told him, “If you think I did it, shoot me.”

Capone, who surely never intended to kill McSwiggin, would finally admit that the prosecutor was sharing in the graft that Al so liberally dispensed. “I paid McSwiggin,” he said. “I paid him a lot, and I got what I was paying for.”

A peace conference in the autumn of 1926 brought relative calm to Chicago gangland. Territories were again delineated; handshakes replaced bullets. The next three years would mark the pinnacle of Capone’s power. Six years after arriving in the city, he owned it.

It was no coincidence that the period also saw the return of William Hale Thompson, Jr., as Chicago’s mayor. A millionaire and the grandson of one of the city’s founders, Big Bill grew up a privileged sportsman, a devotee of cowboy culture.

In 1915 the Windy City elected this confident, windy man as its mayor. Thompson did not quibble about his stand on the dry laws, declaring himself “as wet as the middle of the