Which branch of law defines the rights and duties of individuals?

Substantive law is the branch of law that defines the rights and duties of individuals, as well as the legal relationships among them. It encompasses the rules and principles that determine who may sue whom, what defenses may be used, and what rights individuals have under various circumstances. For example, substantive law covers areas such as contracts, torts, property, family law, and criminal law, all of which articulate specific rights and responsibilities.

While procedural law outlines the methods and processes through which substantive laws are enforced, it does not define the rights and duties themselves. Statutory law consists of laws enacted by legislative bodies, which can include substantive law but does not exclusively define rights and duties. Common law, developed through court decisions and precedents, contributes to the body of substantive law but exists as a separate category that relies on historical judicial rulings. Thus, substantive law is the appropriate choice for defining the fundamental rights and obligations of individuals.