Why did plebeians want a codified law code?

Plebeians wanted a codified law code in the ancient Rome because they felt their legal rights were blocked by the fact that court judgments were made according to unwritten custom preserved only within a small group of learned patricians, so twelve bronze tablets were produced and posted in the Roman Forum, so the plebeians will become acquainted with the law and protect themselves against patricians abuse of power.

during the ming dynasty