The ancient document that outlined the rights of Roman citizens is known as the Twelve Tables. Created in the mid-5th century BC, this legal code was developed to provide transparency and protect the rights of citizens, especially the plebeians, against arbitrary decisions by patrician magistrates. The Twelve Tables addressed various aspects of daily life, including property rights, family law, and legal procedures. This foundational legal framework established principles that influenced later Roman law and helped shape the legal systems in many modern societies, emphasizing the importance of the rule of law.