originally a formal writ issued by the English crown commanding an official to perform a specific act within the duty of his office. It later became a judicial writ issued from the Court of Queen's Bench, in the name of the sovereign, at the request of an individual suitor whose interests were alleged to be affected adversely by the failure of an official to act as his duty required. It is awarded not as a matter of right but rather at the discretion of the court and is thus largely controlled by equitable principles. The writ is not ordinarily granted when an alternative remedy is available, and it is never granted when the official to whom it would be directed has the legal discretion either to perform the act demanded or to abstain from doing so. In Anglo-American legal systems, mandamus is used by courts of superior jurisdiction to compel the performance of a specific act refused by a lower court, such as the hearing of a case falling within the latter's authority.
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