(or mandamus) a final order of a court to any governmental body, government official or a lower court to perform an act the court finds is an official duty required by law. this is distinguished from an alternative writ of mandate (mandamus), which orders the governmental agency, court or officials to obey the order or show cause at a hearing why it should not. the usual practice is for anyone desiring such an order to file a petition for the alternative writ. if the officials do not comply with the order and fail to convince the court that the writ of mandate should be denied, then the court will issue the peremptory writ. in some emergency situations or when there is no conceivable reason for the government not to follow the law, then the peremptory writ will be issued after a notice of hearing without the alternative writ.