For nearly a century, the Federal Bureau of Investigation has been famous for tracking and apprehending gangsters, kidnappers, spies, and, much more recently, international terrorists. The agency itself has done much to promote its successes, helping to embellish its legendary aura. Athan Theoharis, however, contends that a closer look at the historical record reveals a much less idealized and much more disturbing vision of the FBI. Created in 1908 with a staff of three dozen, the FBI has grown to more than 27, 000 agents and support personnel, while its role has shifted dramatically from law enforcement to intelligence operations. Theoharis, America's leading authority on the FBI, assesses the consequences of this shift for democratic politics, showing how the agency's obsession with absolute secrecy has undermined both civil liberties and agency accountability. As Theoharis reveals, FBI history has been marked by operational failures, overrated abilities, and the frequent use of highly suspect means--wiretaps, buggings, break-ins--that challenge the Constitution's guarantee against illegal searches. The agency has also gathered and disseminated derogatory (and often untrue) information in an effort to discredit citizens whose views are seen as "dangerous." Most disturbing, it has drifted toward equating political dissent with genuine subversion, an approach with potentially grave consequences for free and open public discourse. Theoharis also shows that the FBI's vaunted spy-catching prowess has been vastly overrated, from the early days of the "Communist conspiracy" to the more recent Wen Ho Lee and Robert Hanssen fiascos. And he criticizes Hoover's longstanding refusal to admit thatorganized crime actually existed, perhaps due to his preoccupation with the sex lives of public figures like JFK, Martin Luther King, and Rock Hudson, whose amorous escapades he recorded in his "Do Not File" files. More recently, the notorious incidents at Ruby Ridge, Waco,