Common Knowledge(s) #3: Judicial Review, Marriage Equality and the Constitution

A look at the courts of the Australian states and territories.

On July 14, the Victoria Court of Appeal ruled that the mandatory minimum sentences imposed by the legislation were unfair; however, because statutory law trumps common law, the Court of Appeal was forced to give an 18-year-old a mandatory three-year sentence. See 6 News coverage of this case, Buckley vs. the Queen [2022], here. However, this raises the question of whether the courts can ever strike down the legislation.

The “rule of law” is a set of principles that govern democratic countries. One of the most important principles is the separation of powers, which requires that the judiciary, the legislature and the executive be separated from each other. See here to find out how this separation of powers works in Australia. The separation of powers forces each branch of government to limit the others and hold them accountable, through what are known as “checks and balances”. In the case of the judiciary, this power is unimaginatively called “judicial control”.

Section 76(i) of the Australian Constitution allows the Commonwealth Parliament to grant the High Court of Australia jurisdiction over all matters involving the Constitution, known as constitutional law. Parliament has done so in section 30(a) of the Judiciary Act 1903 (Cth). In addition, section 75(v) of the Constitution allows the High Court to hear court cases involving the executive branch of government, where the executive has been accused of breaking the law. Section 76(i) allows the High Court to hear cases under section 75(v) which involve a breach of the Constitution. Under Section 76(i), the High Court may also hear cases relating to Parliament’s breach of the Constitution.

Perhaps the most famous part of constitutional law is section 109 of the Constitution. Section 109 states that if a law of the Commonwealth and a law of a State (or Territory) are inconsistent, the law of the State “shall, to the extent of the inconsistency, be invalid”. This is important in a federal system. If both levels of government can pass laws on the same subjects, Commonwealth law will prevail. This means that if the Commonwealth Parliament had passed legislation banning mandatory minimum sentences, this could be used to prevent the Victorian government from passing these “unjust” laws.

However, like many things in law, it is not that simple. The same federal system that allows Commonwealth law to prevail also limits the situations in which it can prevail. The Commonwealth Parliament can only pass laws on subjects, or leaders of power,’ that it is authorized by the Constitution. It has “exhaustive powers”, because it is possible to write a list of all the subjects on which it can legislate. In contrast, state parliaments have “plenary powers”, as an exhaustive list cannot be written.

There are only a few areas where states cannot legislate at all. But there are many areas in which both levels of government can pass laws, particularly the areas referred to in section 51 of the Constitution. If there is no constitutional head of power that allows Parliament to pass laws on a subject, section 109 is irrelevant. There is no head of power with respect to mandatory minimum sentences. But if there were, that would be where Section 109 would come into play.

A recent and controversial use of this power was in the Same-sex marriage cases (2013). In this case, the Australian Capital Territory attempted to legalize same-sex marriage, defining “marriage” in the Marriage Equality (Same Sex) Act 2013 (ACT) as “the union of 2 persons of the same sex to the exclusion of all others, voluntarily contracted for life”. On the other hand, the Marriage Act 1961 (Cth) used the expression “the union of a man and a woman”. The Commonwealth Government immediately responded by taking the case to the High Court, where it was held that the ACT Act was invalid, as Section 51(xxi) of the Constitution grants the Commonwealth Parliament the power to legislate on marriage. Because the two Acts, which were both legally passed by their respective legislatures, were inconsistent, the Commonwealth won. It should be noted that Article 109 applies to States, not territories, but to Article 28 of the Australian Capital Territory (Self-Government) Act 1988 has the same effect.

4 years later, the Australian public told the Commonwealth government that they believe same-sex marriage should be legal. Section 109 is not concerned with whether a law is moral, only whether it is legal. It doesn’t matter whether ACT residents supported same-sex marriage, or whether it was embraced by their democratically elected legislature; it was not constitutional, so it was invalid.

State and Territory courts, such as the Court of Appeal in Victoria, do not have similar powers over inconsistencies between constitutions and legislation. If a similar federal system existed at this level, with States and Territories sharing legislative authority with local government areas, this might be necessary. Similarly, if states and territories had their own constitutional bills of rights, this power of judicial review might exist.

Judicial review is not concerned with the morality or “correctness” of laws, only with their legality. With respect to the executive branch of government, alternatives to judicial review have been developed, such as “review on the merits”, which focuses more on whether an action is just. However, similar developments have not been made for the judicial review of the legislature, giving the judiciary only limited power to strike down legislation, and even then the power to strike down legislation must come from the Constitutionwhich has more authority than legislation.

Stuart Jeffery is a freelance researcher and digital editor for 6 News. His views on personal social media pages are his own and do not reflect the views of 6 News or our reporters. He respects 6 News’ editorial standards relating to fairness and accuracy.

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Australian Capital Territory (Self-Government) Act 1977 (Cth).

Buckley vs. the Queen [2022] VSCA 138.

Commonwealth of Australia Constitution Act 1901 (Imp), 63 & 64 Vict, c 12.

Commonwealth v Australian Capital Territory (2013) 250 CLR 441; [2013] HCA 55.

Judiciary Act 1903 (Cth).

Marriage Act 1961 (Cth).

Marriage Equality (Same Sex) Act 2013 (LAW).