Government: The government of the ancient Mesopotamians was an unusual form of government. There was a King and nobles who made the law and declared war and decided how to honor the gods. Then there was an assembly of the people who could overrule the king and say, this is not a good law, get rid of it, or we don't want to go to war, so stop it. The kings, if they were wise, would listen to the people.
Sumerian Laws: The Sumerians did not, to our knowledge, write down their laws. The King passed a law, and everyone was expected to learn it and obey it. If you broke the law in Sumer, you would be punished. The punishment was set for each infraction. If you stole something, you were punished according to what you stole. If you offended the gods, you were punished. Everyone knew what the punishment was so there was no escape by saying you didn't know.
Babylonian Laws: The government and laws of Babylon were like the government and laws of Sumer. There was a king and other nobles who ruled with the help of an assembly of the people. The laws of Babylon were taken from the laws of Sumer. Everyone was expected to know and obey the laws. To ensure this and to ensure that the laws were followed by everyone, one of the Kings of Babylon, Hammurabi, had the laws written down on stone tablets. The code of Hammurabi was famous.