J. Edgar Hoover had been director since 1924. He had spent a decade building the Bureau’s professional infrastructure: establishing entrance requirements, creating training protocols, expanding the fingerprint identification division, and working to separate the Bureau’s public image from the corruption and incompetence that had characterized the Justice Department’s law enforcement arm in earlier decades.
The early 1930s had accelerated this transformation. The Kansas City Massacre of June 1933, in which four law enforcement officers and a federal prisoner were killed, had prompted Congressional action expanding federal jurisdiction over crimes involving violence against federal agents and over kidnapping cases. The expansion of FBI jurisdiction was itself partly a product of the pressure created by the Public Enemy cases.
By the time the Dillinger case reached the FBI, the Bureau had the legal authority, the organizational infrastructure, and the political backing to treat it as a showcase for the new federal law enforcement. Director Hoover personally tracked the case’s progress, was briefed on major developments, and was involved in decisions about how to handle particular situations.
The case became, in retrospect, a turning point in the Bureau’s history — not primarily because of the outcome (Dillinger was shot, the case closed) but because of what the coverage revealed about the FBI’s capability and limitations.
The capability was real: the Bureau had the fingerprint database, the laboratory, the informant network, and eventually the operational intelligence to locate Dillinger and act. The limitations were also real: Little Bohemia had demonstrated that tactical execution could fail even when intelligence was sound. The Biograph operation succeeded partly because the intelligence was better (Sage was closer to Dillinger than any previous informant) and partly because the operational planning was more careful.