Joh Bjelke-Petersen, the Premier of Queensland at the time, did not approve of the sale, because he did not believe that Aboriginal people should be able to acquire large areas of land, a view which was reflected in official cabinet policy.

Koowarta initially made a complaint to the Human Rights and Equal Opportunity Commission, on the basis that blocking the sale was discriminatory.

Koowarta presented a case to the Human Rights Commission opposing the policy enacted by the Queensland Government, to block Aboriginal acquisition of large areas of land, arguing that it was discriminatory under sections 9 and 12 of the Racial Discrimination Act 1975.

Section 51 of the Australian Constitution defines the powers of the Australian Government, and Bjelke-Petersen argued that subsection xxvi of that section, which allows the Parliament of Australia to make laws for "the people of any race, for whom it is deemed necessary to make special laws," did not apply to the Act, since it prohibited discrimination against people of all races.

Section 51(xxix) of the Australian Constitution, which simply states that the Parliament has power to make laws with respect to "external affairs" (a term which is left undefined), was put forward as an alternative source of authority for the Act.

The Commonwealth in a submission argued that since the Act gave effect to Australia's international obligations as a signatory to the CERD, it came under the external affairs power.

Three judges (Gibbs, Aickin, and Wilson) adopted a very narrow view, endorsing a test proposed by Dixon, J in R v Burgess; ex parte Henry, which focuses on whether a treaty is "indisputably international".

Three other judges (Mason, Murphy, Brennan) took a wide view, saying that the mere existence of a treaty obligation was sufficient to render the matter an 'external affair', regardless of the particular subject in question.

The deciding opinion was that of Ninian Stephen, who ultimately agreed with Mason, Murphy and Brennan on the facts, but took a somewhat narrow middle path in order to arrive at the same conclusion.

As a result, there was no clear ratio decidendi in the case; at best, a majority of the court might hold that s51(xxix) would support legislation implementing treaties with subject-matter of 'international concern'.

However, on 6 October 2010 Premier Anna Bligh announced that a 75,000 hectares (750 km2) portion of the park would be given over to the Wik-Mungkana peoples as freehold land.