The Psychopath Test by Jon Ronsom

Ronsom, whi has already established an aversion to psychiatry (see "Men Who Stare at Goats") takes on psychopathy in this somewhat scattered but very interesting book.
First he wants to know who these people are. So he goes to prisons in England, Canada and the U.S. Then he takes a three-day seminar from Robert Hare, the leading expert in psychopathy, whose Hare PCL-R Checklist is used by law enforcement agencies in the U.S. and elsewhere to evaluate offenders. Hence the 'test' referred to in the title. Cutting to the chase, it helps but it does not define who is mortally dangerous and who is not. Just who doesn't much care about those who fall out of their personal scope.
Armed with this test, Ronson decides to go out and use it. He tries it out on a man convicted of leading a Haitian death squad (seemingly a good canditdate for a positive score on the test). Then he goes wider. Ronson tests out Hare's checklist on a captain of industry, one of the most notoriously ruthless of American businessmen. At the Florida home of Al Dunlap — the downsizing executive nicknamed "Chainsaw Al" — he notes an abundance of sculptures of predatory animals, teeth bared, claws extended. Dunlap's score on the checklist rises, but the results ultimately fail to fit key points.
Ronson then turns to psychiatry, and the definition of psychopath in the Diagnostic and Statistical Manual of Mental Disorders, known as DSM. Ronson seeks out psychiatrist Robert Spitzer, the editor who oversaw the expansion of DSM-III, which was 134 pages, to the 494-page DSM-IV. The line between pathology and normalcy can be moved, Ronson shows, by something as messy as a room crowded with arguing experts.
A discussion of the value of excessively labeling behavior as pathology is the focus of the end of the book, and overall, this is a very good read.