Common law

Common law (also known as case law or precedent) is law developed by judges, courts, and similar tribunals, stated in decisions that nominally decide individual cases but that in addition have precedential effect on future cases. Common law is a third branch of law, in contrast to and on equal footing with statutes which are adopted through the legislative process, and regulations which are promulgated by the executive branch. In cases where the parties disagree on what the law is, a common law court looks to past precedential decisions of relevant courts. If a similar dispute has been resolved in the past, the court is usually bound to follow the reasoning used in the prior decision (a principle known as stare decisis). If, however, the court finds that the current dispute is fundamentally distinct from all previous cases (called a "matter of first impression"), judges have the authority and duty to resolve the issue (one party or the other has to win, and on disagreements of law, judges make that decision). Resolution of the issue in one case becomes precedent that binds future courts. Stare decisis, the principle that cases should be decided according to consistent principled rules so that similar facts will yield similar results, lies at the heart of all common law systems.

A "common law system" is a legal system that gives great precedential weight to common law. Common law systems originated during the Middle Ages in England, and from there propagated to the colonies of the British Empire. Today, one third of the world's population live in common law jurisdictions or in systems mixed with civil law.

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