Errors as to precedent facts, sometimes called jurisdictional facts, in Singapore administrative law are errors committed by public authorities concerning facts that must objectively exist or not exist before the authorities have the power to take actions or make decisions under legislation. If an error concerning a precedent fact is made, the statutory power has not been exercised lawfully and may be quashed by the High Court if judicial review is applied for by an aggrieved person. The willingness of the Court to review such errors of fact is an exception to the general rule that the Court only reviews errors of law.