This lecture discusses how the US legal system regulates health care. It describes the three branches of government - legislative, executive, and judicial - and how the court system is divided into trial courts that hear evidence and appellate courts that review cases. The lecture outlines the main sources of law and different types of laws, such as civil/private laws that govern relationships between people/organizations and public laws that govern relationships between people and the government. It provides examples of how civil cases involve private parties and criminal cases involve the government and a defendant.