Much of the research about psychopaths had been conducted among prison populations. It's probably necessary to find a "captive" audience for this research—psychopaths (or sociopaths, but I'll call them psychopaths in this post) wouldn't come in for testing and treatment voluntarily, because they don't believe there is anything wrong with them. Dr. Robert Hare estimates that psychopaths (the term he uses) make up 1 percent of the general population of North America, but almost 25 percent of the prison population. Let's turn these figures around. Sometime in October the population of the United States will reach 300 million people. If 1 percent of all these people are psychopaths, that means …
