Explainer: how Australia can legalise same-sex marriage

The legislative reform required to allow same-sex marriage in Australia is not complicated. There is relative consensus on how it can be achieved. And since the High Court’s explanation that federal parliament has the power to legislate with respect to same-sex marriage, the remaining impediments for parliament are political and moral – not legal.

On Monday, Opposition Leader Bill Shorten introduced a bill into parliament to amend the Marriage Act to allow same-sex marriage.

Shorten’s bill is not the first to come before federal parliament that seeks to allow same-sex marriage. Greens senator Sarah Hanson-Young and Liberal Democrat senator David Leyonhjelm have each introduced similar legislation. Bills have come before the previous parliament: another Hanson-Young bill in 2010, a co-sponsored bill of Andrew Wilkie and Adam Bandt in 2012 and Labor MP Stephen Jones' bill of 2012.

Are there any significant legal differences in the three bills currently before parliament? If not, why is Shorten introducing his bill?

The definition of ‘marriage’

“Marriage” is defined in Section 5 of the Marriage Act as:

… the union of a man and a woman to the exclusion of all others, voluntarily entered into for life.

The Howard government inserted the definition of marriage into the act in 2004 to prevent the courts from interpreting marriage more broadly. These amendments also made sure that same-sex marriages conducted overseas would not be recognised as “marriage” in Australia.

Shorten’s bill removes the words “a man and a woman” from the definition and redefines marriage as a relationship between “two people”. The proposed definition of marriage would read:

… the union of two people to the exclusion of all others, voluntarily entered into for life.

Hanson-Young’s bill and Leyonhjelm’s bill also redefine marriage as a union of “two people”.

All three bills make similar minor changes that are necessary to give effect to this change. Other references to “a man and a woman” within the act are replaced with “two people”.

All three bills would also amend the act so that same-sex marriages conducted overseas would be recognised in Australia.

The current act makes a marriage between a brother and a sister void. A change to the definition of “marriage” to include same-sex unions requires this section to be amended so that marriages between two sisters or two brothers are also void. The change is made by making marriages between “siblings” void.

All three current bills make this change to the act. Curiously, the three bills before the previous parliament had not proposed this change.

Will ministers of religion be forced to solemnise same-sex marriages?

Shorten’s bill inserts a note into Section 47 of the act that:

… a minister of religion cannot be required to solemnise a marriage where the parties to the marriage are of the same sex.

The drafting note, while not part of the wording of the section, is intended to assist in the interpretation of the relevant section. It will appear in the act.

This is a slight change from the approach taken in Jones' 2012 bill, where an additional sub-section had been included to make this point expressly. The inclusion of the note is not as much a change in the law as a clarification of the existing law. The act does not currently impose any obligation on religious ministers to solemnise any and every marriage.

The current Hanson-Young bill also recognises that Section 47 does not require religious ministers to solemnise a marriage. To avoid any doubt, her bill expressly states that these proposed amendments to the act are not intended to limit the existing operation of Section 47 in any way. However, the wording within her bill would not appear as a note in the act.

The 2010 Hanson-Young bill did not include this “avoidance of doubt” clause. It comes about after the 2012 Senate Legal and Constitutional Affairs Legislation Committee Report recommended that such a clause be included. It was a feature of the 2012 Adam Bandt-Andrew Wilkie co-sponsored bill.

The Leyonhjelm bill takes a slightly different approach to who must solemnise marriages – and who can decline a request to solemnise a marriage. The bill amends Section 47 so that religious ministers and registered marriage celebrants are not required to solemnise a marriage.

Thus, the Leyonhjelm bill would allow religious ministers and civil celebrants to choose which marriage ceremonies they conduct and to decline those that might be inconsistent with their beliefs. This extends the current law, which grants this discretion only to religious ministers.

However, the Leyonhjelm bill ensures that if a couple cannot find a minister or celebrant to marry them, they will always have the option of having their marriage solemnised by an authorised state or territory officer, who cannot refuse to do so for any reason other than that the marriage would not be a lawful marriage. In this respect, the Leyonhjelm bill is different from the other two current bills.

The Leyonhjelm bill also makes a specific amendment with respect to defence force chaplains. Where a defence force chaplain refuses to solemnise a same-sex marriage on the basis that it is not a marriage between a man and a woman, the chaplain must – if possible – substitute another chaplain who is willing to marry the couple.

What makes the Shorten bill different?

Of the three same-sex marriage bills before parliament, the wording of the Shorten bill and the Hanson-Young bill are the most similar.

There are perhaps two issues – unrelated to the wording – that make the Shorten bill different. These are the timing and who is introducing the bill.

The vote in the Irish referendum has clearly been a catalyst for Shorten’s bill, whereas the senators’ bills predate the Irish vote. That a once religiously conservative country such as Ireland has allowed same-sex marriage has brought the issue back to the centre of public debate in Australia. Polling also shows growing support for same-sex marriage. More than 70% of Australians support it.

That a bill was introduced into the House of Representatives by the opposition leader has led to discussions between the two major parties on whether a bill co-sponsored by both major parties could be introduced.

A private member’s bill introduced by the opposition leader on any topic is unlikely to receive great support from the government. However, a bipartisan bill is likely to have a greater chance of passing parliament. The greatest hurdle remains whether Liberal and National MPs will be allowed a free vote.

Adam Webster does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.