Tasmania Dams

• One reason this case was significant is because it expanded the law-making powers of the Commonwealth.

  • Under Section 51 of the Constitution, the Commonwealth has exclusive powers to make laws regarding ‘external affairs’.
  • The ambiguity of this responsibility was challenged by the Tasmanian government, as 1983 Commonwealth legislation would prevent their damming of the Franklin River, due to inconsistency with obligations to protect natural treasures.
• • The government argued the legislation was ‘ultra vires’, as the matter of dams is not specifically stated in the constitution, and therefore a state power.
  • Ultimately, the High Court ruled in the Commonwealth’s favour, as their interpretation of the ‘external affairs’ power included the ability of the Federal parliament to make laws to implement the obligations of international treaties like the World Heritage Convention.
• Thus, by broadening the interpretation of this power, the Commonwealth was given the ability to move into a law-making area that was previously considered to be a residual power.
• Furthermore, this case was also significant because the expansion of ‘external affairs’ powers has been affirmed in other cases.

  • Despite not being bound by their previous decisions, the High Court has reiterated their interpretation of ‘external affairs’ in cases such as Croome v Tasmania (1997).
  • Giving effect to the Covenant on Civil and Political Rights, Commonwealth legislation would cause discrepancies with Tasmanian law that, at the time, made it a crime for homosexuals to engage in sexual relationships.
• • When Croome challenged the inconsistency, the Tasmanian government argued the Commonwealth’s inability to make laws in this residual area.
  • Although, pursuant to their interpretation of section 51, Tasmanian law would be changed yet again.