<P> Common law (also known as judicial precedent or judge - made law, or case law) is that body of law derived from judicial decisions of courts and similar tribunals . The defining characteristic of "common law" is that it arises as precedent . In cases where the parties disagree on what the law is, a common law court looks to past precedential decisions of relevant courts, and synthesizes the principles of those past cases as applicable to the current facts . 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"), and legislative statutes are either silent or ambiguous on the question, 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). The court states an opinion that gives reasons for the decision, and those reasons agglomerate with past decisions as precedent to bind future judges and litigants . Common law, as the body of law made by judges, stands 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 (the interactions are explained later in this article). </P> <P> The common law--so named because it was "common" to all the king's courts across England--originated in the practices of the courts of the English kings in the centuries following the Norman Conquest in 1066 . The British Empire spread its legal system to its historical colonies, many of which retain the common law system today . These "common law systems" are legal systems that give great precedential weight to common law, and to the style of reasoning inherited from the English legal system . </P>

Is a decision of the us supreme court enacted law or common law