St. Valentine's Day Massacre, 1929

For two and a half years, the unit harassed the Capone organization and collected evidence for prosecution. Relying on information from anonymous tips, paid informants, wiretaps, and other surveillance, the agents raided and destroyed over two dozen breweries and distilleries, including one whose capacity Ness estimated at 20,000 gallons of alcohol per day.

Cultivating favorable coverage, Ness invited reporters to accompany the group on raids. After he publicly denounced a large bribe offer early in 1930, a Chicago Tribune reporter gave the group its popular identity—“the Untouchables.”

The unit's work helped secure prohibition-related indictments against Capone and others. But federal prosecutors believed that tax-evasion charges constituted a stronger case against Capone, and he was never prosecuted for the prohibition violations.

David E. Ruth