Local, Petty Sessions and Small Claims Courts were amalgamated to form the Magistrates Court in May 2005. The reform of the courts followed on from recommendations by the Law Reform Commission, and was the most significant reform of the Western Australian lower court system in over 100 years.

The Magistrates Court has several registries throughout the State, established under under s.8 (1) of the Magistrate's Court Act. The opening of the Stirling Gardens Registry was gazetted on 5 October 2007. The Stirling Gardens Registry only deals with matters within the Court's criminal jurisdiction.