Mandamus

Mandamus was one of the ancient prerogative writs by which the High Court could compel an inferior court, tribunal, or other public body to perform a duty imposed on it by law. It was available where a body had unlawfully refused or failed to act, as distinct from acting unlawfully — the remedy addresses a wrongful omission rather than a wrongful act. The remedy survives in substance today, but under modern procedure it is sought as one of the forms of relief available on an application for judicial review in the High Court, alongside orders quashing or prohibiting unlawful decisions.

Section 31 of the Senior Courts Act 1981 sets out the forms of relief that may be granted on judicial review, including what the statute itself now labels a 'mandatory, prohibiting or quashing order' rather than using the old Latin names (mandamus, prohibition, certiorari). An application for any of these orders must follow the judicial review procedure: the High Court's permission must first be obtained, and the court will only grant permission if it considers the applicant has a sufficient interest in the matter. Because mandamus/mandatory order is a public law remedy, it is directed at public bodies exercising public functions, not at private individuals or companies in the ordinary course of a private dispute.