That's no way to run a world? That's how justice is done in a majority of countries. The juror system is pretty much the best in the world. Do you understand it? It is the very basis of what IS right and wrong. Mankind makes those rules. You think the Aztecs thought their sacrifices were wrong?
That's why jury systems exist. That's why what is "right" and what is "wrong" is determined by the people themselves.