An order, issued originally by the king in England but more recently by a court, commanding a person to do a specific thing or to appear and explain why he or she should not be compelled to do it.
Under the Common Law, the writs of prohibition and Mandamus were alternative writs. In modern systems of court procedure, an order to show cause serves the same purpose. It commands a person to do something or come into court and show cause why he or she should not be made to do it.