The most disturbing thing, I think, with people that do very morally devious things more and more often is to see that they completely feel that they had no choice in the matter.
There's nothing worse than a director who feels more like a cop than a comrade, so I try to never give orders or create an environment where it's 'my way or the highway,' because actually allowing talented people to bring their originality and insight always brings more depth and complexity than if everyone has to do what you tell them to!