Attorney-General (NSW) v Trethowan

The Attorney-General for New South Wales and others appealed to the High Court of Australia from a decision of the Supreme Court of New South Wales. The dispute concerned the validity of two Bills passed by the New South Wales Parliament: one to repeal section 7A of the Constitution Act 1902 (which mandated a referendum for certain constitutional changes) and another to abolish the Legislative Council. The plaintiffs, members of the Legislative Council, sought to restrain the presentation of these Bills to the Governor for assent until they had been approved by the electors, as required by section 7A.

The central legal issue before the High Court was whether the Parliament of New South Wales had the power to enact section 7A of the Constitution Act 1902, which imposed a requirement for a referendum for any Bill seeking to abolish the Legislative Council or repeal or amend section 7A itself. Specifically, the Court had to determine if this provision constituted a valid restriction on the Parliament's legislative power, particularly concerning its ability to amend or repeal its own constitutional provisions, and whether it complied with the requirements of the Colonial Laws Validity Act 1865.

A majority of the High Court, comprising Rich, Starke, and Dixon JJ., held that section 7A, by requiring a referendum for the repeal or amendment of itself, imposed a condition on the manner and form in which a law respecting the powers of the Legislature could be passed. This condition was considered valid under section 5 of the Colonial Laws Validity Act 1865. Furthermore, Rich J. reasoned that by introducing the electorate as a necessary element in the legislative process for abolishing the Legislative Council, section 7A effectively introduced a new constituent part into the legislative body, which the Parliament had the power to do. Consequently, the Bills to repeal section 7A and to abolish the Legislative Council, not having been submitted to a referendum, could not be presented for royal assent. The decision of the Supreme Court of New South Wales was affirmed.