Commonwealth v State of Queensland

The Commonwealth and its Attorney-General brought an action against the State of Queensland and its Commissioner of Income Tax in the High Court of Australia. The dispute concerned the validity of a Queensland state income tax provision that, in effect, increased the tax burden on individuals who received interest from Commonwealth stock or Treasury bonds. The Commonwealth sought a declaration that the Queensland provision was invalid and an injunction to prevent its enforcement.

The court was required to determine two primary legal issues. First, whether section 7(12) of Queensland's Income Tax Acts 1902-1920 contravened section 52B of the Commonwealth Inscribed Stock Act 1911-1918, which stipulated that interest from Commonwealth stock or Treasury bonds should not be liable to income tax unless declared so in the loan's prospectus. Second, if a contravention was found, whether section 52B of the Commonwealth Act was a valid exercise of the Commonwealth Parliament's legislative power under section 51(iv) of the Constitution, which grants power to legislate with respect to borrowing money on the public credit of the Commonwealth.

A majority of the High Court held that section 7(12) of the Queensland Act did contravene section 52B of the Commonwealth Act. The Court reasoned that while the Queensland Act did not directly tax the interest from Commonwealth bonds, it used the receipt of such interest as a factor in calculating a higher rate of income tax on other income. This indirect method of increasing the tax burden due to the receipt of Commonwealth bond interest was considered to be within the prohibition of section 52B, which was interpreted to mean that the receipt of such interest should not be the occasion for any additional tax liability. The Court further held that section 52B of the Commonwealth Act was a valid exercise of the Commonwealth's constitutional power to legislate with respect to borrowing money on its public credit, as it was a necessary incident of that power to protect the terms of its borrowing arrangements from state taxation.

The Court ordered that section 7(12) of the Queensland Income Tax Acts 1902-1920 was invalid in so far as it related to income arising from Commonwealth securities, and granted an injunction restraining the defendants from enforcing that provision.