‘Gangster Hunters: How Hoover’s G-men Vanquished America’s Deadliest Public Enemies’
By John Oller
Dutton, 512 pages

It was July 22, 1934, and the FBI’s war on crime had been going on for more than a year, leaving the federal agents tense and tired, excited but wary. John Dillinger had robbed banks all over America, broken out of jail, and had become a folk hero during a Depression in which many had lost their life savings in bank failures. Now, the FBI had fatally shot him as he was coming out of Chicago’s crowded Biograph movie theater.

With the death of Dillinger, the FBI was close to wrapping up its war that ended the lives of Bonnie and Clyde, Baby Face Nelson, and Pretty Boy Floyd — to name a few of what became known as public enemies. The FBI had struggled, only gradually besting gang members who wielded machine guns and high-powered rifles with remarkable dexterity against poorly equipped and insufficiently trained law enforcement officers.

As John Oller shows, J. Edgar Hoover, essentially a Washington bureaucrat, built up the FBI against the wishes of congressmen and local officials protecting their states rights prerogatives. Under Hoover’s relentless leadership and public relations savvy, the buttoned-down and nattily attired G-men became the heroes instead of the criminals. 

What interests Mr. Oller are those FBI agents whose names until now have largely been erased from history — intentionally by their boss, who wanted to take credit for every gang bust though he was present only once, at the arrest on May 2, 1936, of Alvin Karpis, the most elusive criminal of all. Hoover was there so he could answer the taunts of a congressman who had ridiculed his desk chair direction of the FBI.

Mr. Oller is especially good at re-enacting what it was like to stake out a high-profile criminal. So many things could go wrong. Agents blundered, allowing criminals to outwit them, but often it was a matter of not having enough manpower at a time when the FBI was underfunded and did not have the technology taken for granted now — like helicopters, the tracking of cellphones, and all the apparatus of the national security state gradually established during FDR’s presidency.

Hoover begrudged the success of individual agents, and he never seemed to acknowledge all the factors that could lead to the escape of a criminal — especially the widespread corruption in local police forces that became, in effect, allies of the criminals, tipping them off to the presence of the FBI. 

When criminals were shot, they knew where to seek medical attention from doctors who specialized in treating the likes of Dillinger, who even had a facelift; others had their fingertips shaved or treated with acid in efforts to get rid of their prints.

No self-respecting bank robber in the upper echelons of crime traveled without several sets of license plates and stories that disguised their illicit activities. Repeatedly, when their own vehicles were shot up, they had no trouble stealing cars that had keys in their ignitions.

Many of the kidnappers, holding company owners for ransom, and bank robbers came from poor rural locales, and were not so different in personality and background from FBI agents who grew up firing guns and hunting game.

At the end of this well-told history, we learn that many surviving children of FBI agents helped Mr. Oller show for the first time the courage and determination of those whom Hoover did his best to keep from public view. 

Here is just part of Mr. Oller’s honor roll: “Leslie Kindell, the hidden hero of the search for Bonnie and Clyde; baseball player Tom Connor, who prevented a disaster at the Biograph Theater by adroitly shooing off the Chicago cops; Tom McDade and Bill Ryan, who traded deadly gunfire with Baby Face Nelson during the car chase near Barrington, Illinois.”

What the longer list of FBI heroes discloses is how hard these men had to work together while their chief in Washington berated them for mistakes — or even when they were just victims of bad luck. Perhaps the FBI would never have won its place in the federal bureaucracy without the preening Hoover, but he had to rely on these valiant men to get it done.

Mr. Rollyson is the author of “American Biography.”