The correct answer to this open question is the following.
Although the question doesn't include options, we can say the following.
The current U.S. Law that has basically unchanged when compared to the Justinian Cod is the failure to pay debts.
The Justian Code was a strict set of rules dictated by the Byzantine Emperor Justinian, to maintain proper order and control in the Byzantine Empire.
In the case of current US legislation regarding the paying of debts, there are some legal resources that debtors can use to protect themselves. The common kinds of debt in the US are home loans, school and college loans, and credit card debts, among others. In this case, is when the American citizens can use the Fair Credit Billing Act or the Truth in Lending Act.