A legal system as only as good as those who control it.

One way to define what the law is, is that it's the will of the strong imposed upon the weak. In the Middle Ages for example the "strong" were barons who imposed laws upon the peasants through their men-at-arms.

Today we have various competing legal systems fighting either for global control or defending their local "sovereignty". When we reach the point of one global legal system, we will have found a winner.