So what real thing does this kid have, then? Or what _degree_ is it?
He's also a brat who has learned he can get more of a reaction out of adults by acting in a certain way that they find unsettling, thus reinforcing that behaviour. From the sounds of things, his bad behaviour has been getting reinforced by feelings of specialness ever since he got sent to a psychiatrist at the age of three for being a little more bratty than usual.
At this point, being a brat has got him all the way to being profiled in the New York Times, so I doubt there's much hope for him now. He's internalized "I am a kid who misbehaves, misbehavior makes me special".
This was elementary school since he was shipped off to some special place by middle school. He had two really nice brothers who seemed as relieved as the rest of us when he was gone.
As already recommended in this thread, I urge a viewing of "We Need to Talk about Kevin"
Asshole, brat, jerk ... We all might fall in and out of these fugues as we mature. But, very few of us are evil. You do disservice to those trying to understand these conditions (whether biological or environmental) by minimizing them.