Case Law

The law as established in previous court decisions. A synonym for legal precedent. Akin to common law, which springs from tradition and judicial decisions.

Additional Sources

Law based on judicial decision and precedent rather than on statutes.

Duhaime Legal Dictionary

If a rule of law cannot be found in written laws, lawyers will often say that it is a rule to be found in "case law". In other words, the rule is not in the statute books but can be found as a principle of law established by a judge in some recorded case. Dictionary

Reported decisions of appeals courts and other courts which make new interpretations of the law and, therefore, can be cited as precedents. These interpretations are distinguished from "statutory law," which is the statutes and codes (laws) enacted by legislative bodies; "regulatory law," which is regulations required by agencies based on statutes; and in some states, the common law, which is the generally accepted law carried down from England. The rulings in trials and hearings which are not appealed and not reported are not case law and, therefore, not precedent or new interpretations. Law students principally study case law to understand the application of law to facts and learn the courts' subsequent interpretations of statutes.

Law established by judicial decisions in cases as distinguished from law created by legislation.

Lect Law Library

Also known as Common Law. The law created by judges when deciding individual disputes or cases. Non-statutory law.

Legal principles that are developed by appellate courts when deciding appeals are collectively termed the case law or common law. Since the 12th century, the common law has been England's primary system of law. When the United States became independent, states adopted the English common law as their law. Since that time, decisions by U.S. courts have developed a body of U.S. case law which has superseded English common law in most areas.

The Free (Legal) Dictionary

Legal principles enunciated and embodied in judicial decisions that are derived from the application of particular areas of law to the facts of individual cases.

As opposed to statutes—legislative acts that proscribe certain conduct by demanding or prohibiting something or that declare the legality of particular acts—case law is a dynamic and constantly developing body of law. Each case contains a portion wherein the facts of the controversy are set forth as well as the holding and dicta—an explanation of how the judge arrived at a particular conclusion. In addition, a case might contain concurring and dissenting opinions of other judges.


Case law (also known as decisional law or judicial precedent and often referred to as black-letter law) is the general term for the principles and rules of law set forth in judicial opinions from courts of law. Case law incorporates courts' decisions from individual cases and encompasses courts' interpretations of statutes, constitutional provisions, administrative regulations and, in some cases, law originating solely from the courts. Case law is often published in print law reports or reporters (and increasingly on court websites) to establish precedent - rules to apply in future court decisions dealing with similar situations.