There is no such thing as good or evil, there is only progress, animals kill each other to survive and get stronger, the week die so the strong live. That is nature, that is life.
It was our superior intellect that created morals that separate us from animals and in so doing we risk destroying our species, because we pity the week.
Good and evil are a list of rules, written by however is in charge, if a human is born alone with no one to teach it what is right or wrong by their standards, it reverts back to being an animal only intent on surviving, could you convict such a creature of killing someone any more then you would any other wild animal killing it's prey.