I say as criminals. It may be true that they act as they do because of deficiencies in their brain. That simply means that such a deficiency in their brain makes them more likely to act in an evil way (and not to understand it), however, not that the action is not evil. All of us are born to some extent wanting to do bad things. These people obviously have a very regrettable super-predilection.

In the article, note the following line:

"According to Dr Kiehl, it is part of a pattern of brain activity which proves that psychopaths simply lack an emotional ability, in much the same way others lack intellectual ability. "

Importantly, he does NOT lack intellectual ability. Doubtless he has enough to understand such propositions as, "Society holds murder and rape to be very wrong and will aggressively punish infractions." Indeed, even if "wrong" appears to him as an undefinable and mystifying concept, the latter should be all he needs to know.