Among the most dangerous criminals of the public enemies era was a man who has long hidden in history's shadows: Tom Brown. In the early 1930s, while he was police chief of St. Paul, Minnesota, Brown became a secret partner of the infamous Barker gang. He profited from their violent crimes, he protected the gang from raids by the nascent FBI-and while he did all this, the gangsters gunned down cops and citizens in his hometown.

Big Tom Brown, 6'5" and 275 pounds, continued to enforce St. Paul's corrupt O'Connor system, allowing criminals to stay in the city as long as they paid off the cops and committed no crimes within fifty miles. But in the early 1930s, the system broke down: no longer supported by cash skimmed from illegal booze, gangsters turned to robbing banks, and the Barker gang kidnapped two of the prominent citizens who had been complicit in the liquor trade. Brown was the insider who kept the criminals safe-but for highly political reasons, he was never convicted of his crimes.

Timothy Mahoney tells this fascinating story, details how the fraud was uncovered, and at last exposes the corruption of a secret partnership.