Over the centuries, the law has evolved into a quagmire of rules, statutes, regulations, case law, codes, and opinions that, in many instances, vary from state to state, state court to federal court, and jurisdiction to jurisdiction. Laws serve to control and guide people and entities in relationships, unions, and interactions. Laws are also used to resolve conflicts involving people, corporations, countries, and states. Laws have evolved through the ages and have resulted in major changes in the way people live and work in a modern society.

This chapter introduces the legal nurse consultant to the law, court systems, evidentiary rules, procedural rules, and legal doctrines frequently encountered in medical-legal cases. Legal nurse consultants who master a basic understanding of the law, court systems, evidentiary and procedural rules, and common legal doctrines have greater insight into the legal framework in which their work is conducted, thereby enhancing their value and their ability to assist the attorney in the presentation of a formidable case.