Define: Case Law

Case law is part of common law. It includes judgements, also called precedents, which are followed by all courts in the same jurisdictions. The law is recognized, affirmed, and enforced by the subsequent court. Case law varies from statute laws which are laws enacted by legislatures.

Under some conditions, a judge may decide to rule against established case law in the hopes that the courts will begin to review established precedents which may be outdated given the current societal “climate.” If a judge rules against a precedent this may force the case to be appealed to a higher court and the established law may be overturned.

Case law (also known as decisional law) is the body of reported judicial opinions in countries that have common law legal systems that are published and thereby become precedent, i.e. the basis for future decisions.

In the United States, law derived from judicial decisions is also referred to as common law or black letter law. This type of law operates by application of precedent and is also known as precedential law. Because it is law that is not enacted by a legislature, it is also a type of non-statutory law.

Description

Case law is judge-made law that interprets prior case law, statutes and other legal authority, including legal scholars such as the Corpus Juris Secundum, Halsbury’s Laws of England, or the doctrinal writings found in the Recueil Dalloz and law commissions such as the American Law Institute

In the civil law tradition, case law formally plays a minor role compared to the status of the civil code; however, judicial interpretation of the civil code, interpreting the legal meaning of the code’s provisions, clarifying them, and providing for unforeseen developments, is often referred to as a jurisprudence constante. In France, the jurisprudence constante of the Cour de cassation (for civil and penal cases) or the Conseil d’État (for administrative cases) is in practice equivalent to case law and is of considerable import in certain domains, such as labour law or administrative law. In particular, the Conseil d’État and the Constitutional Council have distinguished “fundamental principles” that statutes and regulations must follow, even when those principles were not explicitly written in statutes.

In the common law tradition, case law regulates, via precedents, how laws are to be understood based on how prior cases have been decided. Case law governs the impact court decisions have on future cases. Unlike most civil law systems, common law systems follow the doctrine of stare decisis in which lower courts usually make decisions consistent with previous decisions of higher courts.

Generally speaking, there is no direct oversight that appellate courts have over a court of record. If a lower court judge acts against precedent and the case is not taken to appeal, the lower court decision will stand. This may occur more frequently than has been documented, as an appeal is usually quite expensive to prepare. Some judges are also known to rule against precedent on principle. A judge (or even an interim appeals court) may rule against a precedent that is outdated. The judge may feel the decision needs to be overturned due to more sophisticated legal reasoning. Such a judge may wish to help the law evolve by ruling against precedent and thereby indirectly inducing a losing party to appeal. The appeals court will then have an opportunity to review the lower court’s decision and may adopt the lower court’s reasoning, thereby overturning previous case law. This may also happen several times as the case works its way through intermediate appellate jurisdictions.

A famous example of this evolution in jurisprudence was by Lord Denning, first of the High Court of Justice, later of the Court of Appeal, in his development of the concept of estoppel, starting in the world-renowned High Trees case: Central London Property Trust Ltd v. High Trees House Ltd (1947) K.B. 130.

The different roles of case law in civil and common law traditions create differences in the way that courts render their decisions. Common law courts generally explain in detail the rationale behind their decisions with numerous citations to previous decisions and other authorities (called ratio decidendi). By contrast, decisions in the courts of most civil law jurisdictions are generally very short, referring only to the statutes used. The reason for this difference is that, in these civil law jurisdictions, the tradition is that the reader should be able to deduce the logic from the decision. Courts in civil law jurisdictions also render their decisions so that, in some cases, it is somewhat difficult to apply previous decisions to the facts presented in future cases. Some pluralist systems, such as Scots law in Scotland and so-called civil law jurisdictions in Quebec and Louisiana, do not follow these traditions as they are jurisdictions that have been influenced heavily by the Anglo-American common law tradition; however, their substantive law is firmly rooted in the civil law tradition. Because of their position between the two main systems of law, these types of legal systems are sometimes referred to as mixed systems of law.

Another difference is that law professors in common law traditions play a much smaller role in developing case law than professors in civil law traditions. Because court decisions in civil law traditions are brief and not amenable to establishing precedent, much of the exposition of the law in civil law traditions is done by academics rather than by judges; this is called doctrine and may be published in treatises or in journals such as Recueil Dalloz in France. In common law, the practice has evolved in the other direction; thus, at the turn of the twentieth century, it was very rare to see an academic writer quoted in a legal decision (except perhaps for prominent jurists such as Coke and Blackstone). Today, academic writers can be cited in legal decisions as authorities; often, they are cited when judges are attempting to find reasoning that has yet to be adopted by any other court or because their restatement of the law is more compelling than the ratio of precedent. Thus, common law systems are adopting one of the approaches long common in civil law jurisdictions.

In federal or multi-jurisdictional law systems, there may be conflicts between the various lower appellate courts. Sometimes these differences may not be resolved, and it may be necessary to distinguish how the law has been applied in one district, province, division, or appellate department. Usually, only an appeal accepted by the court of last resort will resolve such differences, and for many reasons, such appeals are often not undertaken.

This site contains general legal information but does not constitute professional legal advice for your particular situation. Persuing this glossary does not create an attorney-client or legal adviser relationship. If you have specific questions, please consult a qualified attorney licensed in your jurisdiction.

This glossary post was last updated: 9th April, 2024.