Karma is our judge

"If more people believed in the law of karma, we would never need a police force or peace treaties. But without an inner conviction that nobody can escape the consequences of their actions, even if we employ many types of external means in order to enforce the law, we will never be able to build a peaceful society. Modern societies use very sophisticated equipment to monitor and identify criminals. But the more complicated and fascinating our equipment is, the more sophisticated and determined the criminals become. If human society is to improve, it is not enough to enforce external laws. We need to have recourse to our inner judge."
-the Dalai Lama