A more thorough explanation:

Definition: Lex Duodecim Tabularum is the earliest surviving legislation enacted by the Romans, written on 12 tablets in the 5th century B.C. It is also known as the Twelve Tables. The Tables set out many rights and duties of Roman citizens, including debtors' rights, family law, wills, torts, civil procedure, and some public law. They substituted a written body of laws, easily accessible and binding on all citizens of Rome, for an unwritten usage accessible to only a few.

Example: One of the laws in the Twelve Tables stated that if a person was in debt and could not pay, they could be taken as a slave by their creditor. This law protected the creditor's rights to get their money back, but also limited the amount of time a debtor could be held as a slave.

Explanation: This example illustrates how the Twelve Tables set out the rights and duties of Roman citizens, including debtors' rights. It shows how the law protected both the creditor and the debtor, and how the law was written down and accessible to all citizens of Rome.