Same sex marriage is not currently legal. This extends even to same sex marriages from other countries, which "must not be recognised as a marriage in Australia".
At both the federal and state levels, there is broad support for officially changing your gender.
There is case law affirming the marriage of a transman and a woman as valid.
But how does Australia law consider a marriage between two persons, who at the time of their marriage were officially identified as a man and a woman, but subsequently one of whom transitioned?
If they officially change their gender, and so are considered by law to be that new gender, is their marriage, which is now effectively a same sex marriage, still considered a valid marriage?
Or, in the states with civil unions, would the couple now be considered only to be in a civil union rather than a marriage? (And for the states without civil unions, would they be considered to be in only a de facto relationship?)