Quantum meruitQuantum meruit is a Latin phrase meaning "what one has earned". In the context of contract law, it means something along the lines of "reasonable value of services". In the United States, the elements of quantum meruit are determined by state common law. For example, to state a claim for unjust enrichment in New York, a plaintiff must allege that (1) defendant was enriched; (2) the enrichment was at plaintiff's expense; and (3) the circumstances were such that equity and good conscience require defendants to make restitution.
Equity (law)In the field of jurisprudence, equity is the particular body of law, developed in the English Court of Chancery, with the general purpose of providing legal remedies for cases wherein the common law is inflexible and cannot fairly resolve the disputed legal matter. Conceptually, equity was part of the historical origins of the system of common law of England, yet is a field of law separate from common law, because equity has its own unique rules and principles, and was administered by courts of equity.
Court of ChanceryThe Court of Chancery was a court of equity in England and Wales that followed a set of loose rules to avoid a slow pace of change and possible harshness (or "inequity") of the common law. The Chancery had jurisdiction over all matters of equity, including trusts, land law, the estates of lunatics and the guardianship of infants. Its initial role differed somewhat: as an extension of the lord chancellor's role as Keeper of the King's Conscience, the court was an administrative body primarily concerned with conscientious law.
Common lawIn law, common law (also known as judicial precedent, judge-made law, or case law) is the body of law created by judges and similar quasi-judicial tribunals by virtue of being stated in written opinions. The defining characteristic of common law is that it arises as precedent. Common law courts look to the past decisions of courts to synthesize the legal principles of past cases. 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.
English lawEnglish law is the common law legal system of England and Wales, comprising mainly criminal law and civil law, each branch having its own courts and procedures. Although the common law has, historically, been the foundation and prime source of English law, the most authoritative law is statutory legislation, which comprises Acts of Parliament, regulations and by-laws. In the absence of any statutory law, the common law with its principle of stare decisis forms the residual source of law, based on judicial decisions, custom, and usage.
