British journalist Jon Ronson is obsessed with obsessives. He's best known for writing the book behind the George Clooney film "The Men Who Stare At Goats." In his latest book, Jon Ronson has turned his own obsessive eye toward psychopaths. The book is called "The Psychopath Test."

Identifying a psychopath is not always easy, says Ronson, "because psychopaths, unlike sufferers of most mental disorders, seem completely normal."

So a Canadian psychologist, Robert Hare, developed a checklist of traits that are typical to psychopaths. These include a lack of remorse, pathological lying, superficial charm, sexual promiscuity and manipulation. Characteristics like impulsive behavior and need for stimulation are also on the list.

Ronson points out many of the items are common to healthy people, as well. In order to be diagnosed you need to display at least 15 items on the list. He also notes that if you ask the right questions psychopaths will often reveal themselves in their answers. "I can't tell you the number of psychopaths I've now met who will say practically identical things."

For instance, Ronson says most psychopaths he interviewed say they felt it was important to get people to like them so the psychopath can manipulate them. And he said when you ask a psychopath if they were a bully in school, the subject often says yes.

"I'll ask them how it felt to be a bully. And they'll say, 'it felt good.' I'll ask them, when you think back on it now, how does it feel? And they will say 'yeah, it still feels good.'"

Psychologists think the signs of pathological behavior tend to emerge in a person at around 10 years of age. Ronson says these individuals aren't just children who get in trouble. "We're talking about extreme behavior, breaking a kid's arm, torturing animals, ending up in juvenile court."

As they mature, many psychopaths develop criminal records. While psychopaths make up less than 1 percent of the general population, studies have shown that one of four inmates is a psychopath. But more surprisingly, a significant number end up rising to the top of high-powered professions.

Ronson says perhaps 4 percent of the people at the top of the corporate ladder are psychopaths. "So you are four times more likely to find a powerful psychopath than a walking around psychopath," says Ronson.

One of the stranger characteristics of psychopaths is their choice of pets. Ronson says they are almost never cat people. "Because cats are willful," he explains.

Psychopaths gravitate toward dogs since they are obedient and easy to manipulate. Ronson says he spoke with individuals who would qualify as psychopaths who told him they aren't sad when they hear about people dying. "But they get really upset when their dogs die because dogs offer unconditional love."