As we've said, the DSM-V was still in the works at press time. But they had released some preliminary materials about how they're changing diagnoses for personality disorders, and one important note is that "antisocial personality disorder" is now the catchall for psychopathy, too. Basically, this means you won't get a diagnosis of being a "psychopath" from your psychiatrist, but of having "antisocial personality disorder." (A little more on how you can have the behavior traits of a psychopath later.)
However you categorize it, some antisocial traits are pretty intense. People with antisocial personality disorder might display what the DSM-V refers to as "callous behavior," including a lack of guilt or remorse about their negative actions. They might manipulate people to achieve their own ends, using dishonest methods of integration or deception. They might anger at really small insults. On top of all this, they could also be disinhibited, meaning they might be impulsive or take risks without regard to consequences.
Even more disturbing is that these behaviors aren't just in adults. There's been an interest in studying children with antisocial personality disorder, especially those with strong "callous-unemotional" (CU) traits. Those traits -- the ones that basically make someone cold and calculating as opposed to impulsive and unthinking -- help construct a guideline for a psychopath. The fact that children display them is, of course, controversial -- lots of children act out behaviors that could be construed as antisocial. The difference is interesting; one study noted that nearly every psychopathic adult was antisocial as a child, while half the children with high antisocial measures didn't become psychopaths. So an antisocial child won't necessarily become a psychopath, but if you've been deemed a psychopath you're going to display antisocial behavior as a youngster [source: Kahn].
So do these psychopaths, who display antisocial behaviors at a young age, give us evidence that there are some people who just do not have the psychological -- or biological -- capacity to accept they're not above the rules? Perhaps. More tellingly, it probably shows us that if people can corral these instincts in ways we find socially acceptable (amassing power or money) as opposed to deplorable (violence), we're more than willing to celebrate breaking the rules.