Defining a marriage

The classic definition of marriage was formulated by Lord Penzance in the case of Hyde v Hyde when he said: "I conceive that marriage, as understood in Christendom, may for this purpose be defined as the voluntary union for life of one man and one woman, to the exclusion of all others."

The ACT Government originally introduced legislation into its Legislative Assembly to allow people to register a civil union to provide the “functional equivalence” of marriage.

It later removed provisions automatically empowering civil celebrants to conduct civil unions to head off a Federal Government threat to the override the law.

It also inserted a provision reading:

A civil union is different to a marriage but is to be treated for all purposes under Territory law in the same way as a marriage.

Prior to 2004 there was no legislative definition of what is a marriage in Australia.

However, the Federal Parliament passed the Marriage Legislation Amendment Act 2004 to define a marriage as a union between a man and a woman to make clear (as the prime minister put it) “that that is our view of a marriage and … the definition of a marriage that should rest in the hands ultimately of the parliament of the nation and should not over time potentially be subject to redefinition or change by courts”.

There were probably good grounds to do this if that is your view on what constitutes a marriage.

The case of Singh v the Commonwealth considered whether the meaning of the word “alien” had altered since the constitution commenced operation in 1901.

In a footnote to the case, the High Court indicated the meaning of the term “marriage” could have changed, such that the concept of marriage could, by reason of changing circumstances, extend to a voluntary and permanent union between two people.

And in re Wakim; ex Parte McNally, a case dealing with the otherwise esoteric subject of whether a federal court could be vested with the powers of a state supreme court, Mr Justice McHugh said it was arguable that "marriage" now means, or in the near future may mean, a voluntary union for life between two people to the exclusion of others.

The Australian constitution confers on the Federal Parliament power to make laws about marriage and divorce and matrimonial causes.