The High Court is the highest court in Australia and is primarily involved in cases regarding the Commonwealth and/or the Constitution.
The High Court has a unique role due to it's jurisdiction outlined in sections 75 and 76 of the Constitution, for example, in Section 75 the High Court has the jurisdiction to hear in matters regarding the Commonwealth, such as a person suing the Commonwealth or on behalf of the Commonwealth. Section 76 outlines that the High Court may make laws regarding the interpretation of the Constitutions if a relevant case comes before it.
The preservation of the states law making power was paramount and known as the 'reserved powers doctrine' it was not until 1920 after the resolution of the Engineer Case that the High Court adopted a broader approach in the interpretation of the Constitution and that the reserved powers doctrine was rejected.
Due to the rejection of this reserved powers doctrine the High Court has shifted the balance of power in favor of the Commonwealth, this is seen during the 1983 Tasmanian Dams Case where the Commonwealth utilized an international treaty which nominated that the specific area where the Tasmanian Government planned to build the damn was protected and thus passed the World Heritage Properties Conservation Act on the basis of the treaty. The Tasmanian Government brought this case before the High Court citing that the Commonwealth had overstepped it's law making powers, however, it was found that the Commonwealth could indeed act through it's external affairs power despite Section 51 of the Constitution.
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