A judicial opinion is a form of legal opinion written by a judge or a judicial panel in the course of resolving a legal dispute, providing the decision reached to resolve the dispute, and usually indicating the facts which led to the dispute and an analysis of the law used to arrive at the decision.
Substantive law is the set of laws that governs how members of a society are to behave. It is contrasted with procedural law, which is the set of procedures for making, administering, and enforcing substantive law. Substantive law defines rights and responsibilities in civil law, and crimes and punishments in criminal law, substantive equality or substantive due process. It may be codified in statutes or exist through precedent in common law. Substantive laws, which govern outcomes, are contrasted with procedural laws, which govern procedure.
Henry Sumner Maine said of early law, "So great is the ascendency of the Law of Actions in the infancy of Courts of Justice, that substantive law has at first the look of being gradually secreted in the interstices of procedure; and the early lawyer can only see the law through the envelope of its technical forms."