By Professor Michael Crommelin AO
The Minerals Resource Rent Tax Act 2012 (Cth) (MRRT Act) has been surrounded by political and legal controversy throughout its short life. The High Court’s unanimous rejection of a recent constitutional challenge has resolved the legal controversy. It remains to be seen whether, and when, the incoming Federal Government may resolve the political controversy by fulfilling its election pledge to repeal the Act.
In Fortescue Metals Group Ltd v Commonwealth  HCA 34, the plaintiff challenged the constitutional validity of the MRRT Act and three related Acts which imposed the MRRT (MRRT Legislation) in proceedings commenced in the High Court of Australia. The MRRT Act provides that a miner is liable to pay minerals resource rent tax (MRRT) assessed in accordance with the MRRT Act.
The plaintiff argued four grounds for invalidity of the MRRT Legislation: (1) discrimination between States contrary to s 51(ii) of the Constitution; (2) preference to one State over another contrary to s 99 of the Constitution; (3) contravention of the Melbourne Corporation doctrine established in the State Banking Case  HCA 26; and (4) contravention of s 91 of the Constitution which confirms the authority of a State to grant aid to mining. It is notable that the plaintiff did not invoke s 114 of the Constitution which prohibits the imposition by the Commonwealth of any tax on property of any kind belonging to a State.
The challenge failed on all grounds. Continue reading