Same sex marriage could become a constitutional battleground

by Sarah Joseph

On the weekend it was reported that Tasmania intends to legalise same sex marriage despite the Commonwealth Marriage Act 1961 defining “marriage” as being between a man and a woman. Given that apparent discrepancy, does Tasmania have the power under our Constitution to pass a same-sex marriage law? I will briefly answer this question below. I also refer people to the detailed advice on this matter given by Professor George Williams in 2005.

Australia is a federation. Under our Constitution, power is split between the federal government (“the Commonwealth”) and the States. Most of the federal government’s powers are spelt out in section 51. Under s. 51(xxi), the Commonwealth has power over the subject matter of “marriage”: this provision provides the Commonwealth’s authority to enact the Marriage Act. However, the powers in s.51 are “concurrent” powers, meaning they are shared between the Commonwealth and the States. Hence, the States too have power over marriage.

Given that the Commonwealth and the States can legislate in the same area, there is the potential for inconsistency. Section 109 of the Constitution tells us how to resolve inconsistencies. Basically, the Commonwealth law will prevail.

So how is “inconsistency” determined? Is it likely that the Tasmanian Act would be struck down as being inconsistent with the Commonwealth Act? I speculate on this below, though it is acknowledged that there is as yet no draft of the proposed Tasmanian law. Bills, which have since lapsed, circulated in 2005 and 2008.

The first test of inconsistency is to ask whether simultaneous obedience is impossible. Does one law compel what the other demands? This test will not apply. For a start, neither the Commonwealth Act or any proposed Tasmanian Act will compel anybody to get married.

The second test is to ask whether one law confers a right taken away by the other. Certainly, the Tasmanian law would grant a right for same sex couples to get married which is not recognised under Commonwealth law. But the Commonwealth does not take away such a right: it does not prohibit same sex marriage at the State level. The Marriage Act has nothing to say about that matter.

The most likely source of inconsistency, if one exists, lies under the third test of “cover the field” inconsistency. Under this test, a State law will be deemed to be inconsistent if it is found that the Commonwealth intended for its law to be the sole law on the topic in question (ie. it intends to “cover the field”).

With regard to the Commonwealth’s intention, section 6 of the Marriage Act explicitly preserves the validity of State and Territory laws relating only to the registration of marriage. Section 6 therefore seems to implicitly exclude the validity of State and Territory laws relating to other aspects of marriage. That is, the Commonwealth has signalled an intention to cover the field of all aspects of marriage besides registration. Which is not promising for the Tasmanian law.

But what in fact is “the field” of the Commonwealth law? Identifying the field (ie the topic of a law) for the purposes of section 109 is notoriously unpredictable.

If the field is “marriage”, then the Tasmanian law would be in constitutional trouble. However, Professor Williams suggests that the field is in fact “opposite sex marriage”, thus leaving the field of “same sex marriage” open for the States. In this regard, he points to the parts of the Commonwealth Act dealing with the recognition of marriage solemnised in foreign countries. Section 88EA makes it clear that same sex marriages conducted overseas are not recognised as “marriages” under the Commonwealth law. Given the Parliament clearly turned its mind to this issue, it is significant that the law says nothing about the recognition of same sex marriages conducted in Australia. That may indicate that that field was simply vacated for the States. On the other hand, given that s88EA deals to a small extent with same sex marriage, that may make it more difficult to argue that the field of the law is confined to “opposite sex marriage”.

The explicit reference to marriage being between a man and a woman in the Marriage Act was introduced by amendments in 2004, and was clearly designed to head off arguments that the Act allowed same sex marriage. Ironically, if Professor Williams is correct, the Howard government amendments may also have the effect of reducing the field of the Commonwealth law, and opening up space for Tasmania to fill.

There are international precedents for same sex marriages being performed at a provincial rather than national level. Same sex marriage is permitted and recognised in a number of US states, but not at the federal level. They are also performed in Mexico City, and these marriages must be recognised throughout Mexico.

If Tasmania is to pass the proposed legislation, it will complete a remarkable journey. Tasmania was the last State to decriminalise same sex relations. In 1994, those laws were found by a United Nations body to breach Australia’s international human rights obligations in Toonen v Australia. The State government only reluctantly repealed the law in 1997 when it became clear that they were unconstitutional, as the Commonwealth had overriden them in 1994 in response to the UN decision. Now it seems that Tasmania may be the first domino to drop in recognising same sex marriage.

Such a law will likely face constitutional challenge, and it is not certain that it would survive. However, any victory by same sex marriage opponents could well be short-lived, as the momentum towards acceptance of same sex marriage in this country seems unstoppable.

Postscript: (warning – this is probably more legalistic than most other posts on this site)

The above piece was originally posted in The Conversation on 6 August. It gave rise to a lively Twitter discussion of the ramifications of the relevant constitutional arguments.

Another Conversation piece by Professor Anne Twomey raises another possible constitutional argument. The Commonwealth Parliament only has the powers conferred upon it by the federal Constitution. If a power is not found in the Constitution, the federal Parliament does not have it. One argument could be that its “marriage” power in s 51(xxi) does not envisage laws permitting marriage between people of the same sex. That is, perhaps it could be argued that “marriage” for constitutional purposes means only a union between a man and a woman (the likely meaning of the term when the Constitution was adopted in 1901), and it cannot be redefined to expand the meaning of s.51(xxi). Certainly, this argument has been raised by Father Frank Brennan in the past. I will not here speculate on the likely success of such an argument, except to say that High Court decisions can often take one by surprise.

What would be the ramifications of such an argument, if it was accepted by the High Court? It would mean that the Commonwealth Parliament would lack power over same sex marriage. The current federal law could not purport to cover the field of same sex marriage, so the Tasmanian law would be valid. The fact of the Tasmanian law calling such unions “marriages” would be irrelevant. The “marriage” power in s51(xxi) of the Constitution draws boundaries around federal powers rather than State powers. State powers go beyond those listed in the Constitution.

But the ramifications would go much further than that. As just stated, the Commonwealth Parliament would lack the power to legislate over same sex marriage, unless that power could be shoehorned into another one of its constitutional powers (eg another section within s.51). Such a decision would be a huge symbolic blow to proponents of same sex marriage, as the High Court would have ruled that such unions are not seen in constitutional law as “marriages”. It would reinforce arguments that same sex unions and opposite sex unions are not equal, or if they are equal they are certainly separate. “Separate but equal” rightly gives rise to feelings of revulsion.

The argument probably cannot be avoided. If it is not raised in a constitutional challenge to the Tasmanian law, it will likely run in a constitutional challenge to any future federal law. The difference would be that the argument preserves the constitutionality of the Tasmanian law but it undermines the constitutionality of a federal law. Supporters of a Tasmanian law would have to think long and hard before running an argument that might win a battle but lose a war.

A related concern arises over the arguments regarding s109 and the “fields” of the laws (the argument discussed above from Professor George Williams). On Twitter, people have raised concerns with me that these arguments also reinforce the idea that same sex marriage and opposite sex marriage are “separate”, even if they might be “equal” too. If true, there is again an unintended consequence in trying to maintain the constitutionality of a Tasmanian law for the broader cause of marriage equality in Australia.

The constitutional question discussed in the original post is “What is the field of the Commonwealth law”, followed by a question of whether the State law trespasses on that field. The federal law as it stands “separates” same sex and opposite sex marriage by excluding the former from its definition of marriage. I’m not sure that that separation is further entrenched or exacerbated by an argument that the federal law therefore only covers a narrow field of “opposite sex marriage” rather than the broader field of “marriage”. After all,”fields” for the purposes of s.109 have historically been drawn both narrowly or broadly – the identification of a field is a technical legal exercise rather than a moral statement about the nature of the identified fields of the respective federal and State laws.

However, I concede that an argument based on “separate fields” could give the appearance of reinforcing “separateness” and “difference”, given the arcane nature of legal argument and legal reasoning.  In which case there is a Catch 22 that the arguments that most support marriage equality may be the arguments that least support the validity of any Tasmanian law on same sex marriage.

As a final note, I add that some colleagues have suggested that the Howard government amendments of 2004 were clearly designed to prohibit same sex marriage in Australia. In which case the High Court, in interpreting the Act, would likely give effect to that intention and interpret it as covering the field of all marriage. Perhaps the reason why the Act makes no mention of same sex marriage in the States (as opposed to those conducted overseas) is that it was simply assumed that such marriages would not exist, as they were effectively excluded from existence under s.109.

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