Representing the Logic of Statutory Rules in the United States, Vern R. Walker, Bernadette C. Lopez, Matthew T. Rutchik, and Julie L. Agris. Chapter 13 in the volume “Logic in the Theory and Practice of Lawmaking” (Michał Araszkiewicz and Krzysztof Płeszka, eds.) (Springer, 2015).
This chapter presents one method of representing the logical structure of systems of legal rules, as they are established by statute in the United States. The chapter uses default logic and “rule trees” to reflect the dynamic and pragmatic context in which legal rules are used, as well as the interplay among legal rules, policy objectives and evidence. Rule trees also capture such important sub-structures as relevant-factor rules and legal presumptions. They are also operational structures available for software computation or for exchange in digital form, and help legal practitioners organize evidence and arguments. Examples throughout are drawn from the statute governing the Vaccine Injury Compensation Program (VICP), which provides compensation to persons who have sustained vaccine-related injuries. Although the examples are from this particular statute, the default-logic framework is applicable to any other statute in the United States and to those in many other jurisdictions.