The Victorian Government has introduced a Bill, the Births Deaths and Marriages Registration Amendment Bill 2016, to amend its law on birth certificates to allow changing the gender on the certificate to be made easier. (The Bill was approved by the Lower House on 15 Sept 2016 and is awaiting consideration by the Legislative Council.) There are many problems with the policy represented by this legislation (see a good summary from Murray Campbell, “Victorian Government and Birth Certificates” Oct 26, 2016)). But what I want to focus on here is the interaction of the new law with the law on marriage. In my view the law will create a host of legal uncertainties at best, and is quite likely to be unable to achieve its apparent aim of allowing Victorians born in one sex to live for all purposes as if they were of the other sex.Victorian law, like other State laws, currently allows a person to change the sex which is recorded on their birth certificate. But, again like other laws, they can only do so after appropriate medical procedures have been carried out (presumably by doctors who have given long and careful consideration to the need for such procedures and their likely impact on the patient.) In addition, such procedures and change to a birth certificate cannot take place if a person is married. (See the requirements set out in the current version of s 30A of the Births Deaths and Marriages Registration Act 1996 (Vic), referring to an “unmarried” person who has undergone “sex affirmation surgery”, meaning “a surgical procedure involving the alteration of a person’s reproductive organs carried out for the purpose of assisting the person to be considered to be a member of the opposite sex.”)
The reason behind the requirement that a person be unmarried is fairly clear: there is one uniform law governing the law of marriage in Australia at the moment, the Marriage Act 1961 of the Commonwealth. Under that Act, s 5(1) defines “marriage” as:
the union of a man and a woman to the exclusion of all others, voluntarily entered into for life.
Hence it was no doubt thought inappropriate, to say the least, to allow a man who is married to a woman, to undergo an apparent “sex change” so that now that person is regarded as a woman. This would result in a situation (if the change were legally effective under Commonwealth law) where a woman was married to a woman, which would be inconsistent with the Commonwealth marriage law.
But the proposed amended s30A deliberately refers to neither of those preconditions. It will read, if enacted:
(Proposed) 30A Application to alter record of sex in person’s birth registration
(1) A person who is aged 18 years or over may apply to the Registrar for the record of the person’s sex in the person’s birth registration to be altered if—
(a) the person’s birth is registered in Victoria; and
(b) the person believes the person’s sex to be as nominated in the application; and
(c) the record of the person’s sex has not been altered within the 12 months preceding the date of making the application.
There is no requirement that a person be unmarried, and in support of their application all that the new legislation requires, under proposed s 30A(4), is a “supporting statement” by someone who is over 18 and has known the applicant for change for more than 12 months. It will be noted that repeated applications may be made, once a year if desired.
Apart from the other problems with this system, then, following the change of certificate (which may or may not be accompanied by any outward signs, and certainly does not need to be accompanied by surgery or medical advice), what was a marriage between a man and a woman will now be, apparently, a marriage between a woman and a woman, or a man and a man.
But Australia does not recognised same sex marriage at the moment. There seem to be two options were this legislation to be used by a married person : either the Victorian law is effective to change a person’s legal sex for all purposes of the law; or it is not. Let’s consider the ramifications of each option.
1. Suppose Victorian law will change sex for all purposes
Suppose that upon the change of gender on the birth certificate taking place, this is legally effective to change the person’s sex for the purposes of the Commonwealth law regarding marriage. But on this logic, there can no longer be a “marriage” under Commonwealth law. Hence it may be argued that this has now rendered the marriage “void”.
There is a difficult question here as to whether a decree of “nullity” would be available in relation to the marriage once a legal sex change had taken place. Under the Marriage Act 1961 s 23B there are a limited number of grounds on which a marriage which has taken place after 7 April 1986 is “void”. (The date is simply the date on which amendments to the Act expanding the criteria for recognition of some overseas marriages took place. There was no change to the law concerning domestic marriages in Australia.)
The grounds on which a marriage is explicitly said to be void under s 23B are: prior lawful marriage; prohibited relationships; failure to comply with formalities; lack of proper consent; parties not of marriageable age. The section concludes with the words “and not otherwise”. An application for a decree of nullity under s 51 of the Family Law Act 1975 (Cth) must be based on the ground that “the marriage is void”.
Hence it seems arguable that a decree of nullity could not be sought in relation to a “marriage” which no longer satisfied the definition of the status in s 5 of the Marriage Act because one of the parties had now legally changed their sex. However, under s 113 of the Family Law Act 1975 a “declaration” may be made in cases falling within para (b) of the definition of “matrimonial cause” within s 4(1) of that Act, which includes “(b) proceedings for a declaration as to the validity of: (i) a marriage”. So it seems fairly clear that a declaration of the validity of the marriage could be sought, and if Victorian law had had the effect of changing the person’s legal sex for the purposes of the law of marriage, then the marriage would from that moment on become “invalid”.
Interestingly, similar issues have been vexing the courts in the United Kingdom in recent years. In the UK Supreme Court case of MB v Secretary of State for Work and Pensions  UKSC 53 (5 July 2016) a male-to-female transsexual who had undergone all relevant surgical procedures wanted to be recognised as a woman for the purposes of receiving a pension (provided at different ages for men and women). The applicant had been married to a woman before undergoing the surgery. She could have registered a gender reassignment under the relevant UK law but (at the time which was relevant) only if she was unmarried. She refused to obtain a decree of nullity (which the law explicitly provided for), saying that for “religious reasons” she and her wife wanted to remain married. She claimed that, by imposing the condition that she be unmarried before her gender change could be recognised, the UK were in breach of the European Convention on Human Rights.
The UK Supreme Court were deeply divided on the matter, and in the end referred it to the European Court of Justice for their advice. But in doing so Lady Hale, who wrote the judgment for the Supreme Court, noted that in previous decisions the European Court of Human Rights had upheld as valid laws in other countries imposing a “marriage condition” on official gender reassignment recognition:
The reason was that, although the Convention requires states to recognise the acquired gender of transsexual persons, it does not require them to allow marriages between same sex couples. In the absence of such a requirement, a state which does not recognise same-sex marriages has a legitimate interest in maintaining the traditional concept of marriage between a man and a woman. (at para 16(5), summing up the arguments of the UK Secretary of State)
It would seem to similarly be the case here, that while Australia maintains the traditional concept of marriage between a man and a woman, the Commonwealth has an interest in not allowing apparent “same sex marriages” to be created by a sex change procedure by one party.
2. Suppose the change under Victorian law will not be recognised by the Commonwealth
Alternatively, and more likely, the better view may be that the Commonwealth is not obliged to recognise for the purposes of its law, a “change” made in such a way under Victorian law. In this case any prior marriage will still be intact, but the “woman” who has undergone the certificate change will still be regarded as a man for the purposes of Commonwealth law.
It may be noted the decision of the Full Court of the Family Court in Attorney-General (Commonwealth) v Kevin  FamCA 94, (2003) 172 FLR 300 says that sex can be changed for the purposes of marriage. While this is true, that case involved a full sexual reassignment surgery and a long period of time lived as the new sex. Neither of those things is required under the Victorian law. Indeed, in its decision in Kevin the Full Court explicitly noted that:
the status of pre-operative transsexual persons is not directly in issue. (at 172 FLR, 313)
Indeed, that the Court in Kevin took so long in discussing the issues and coming to a conclusion, where the applicant had already undergone surgery and had their birth certificate changed under NSW law, demonstrates clearly that status as a man or woman for the purposes of Commonwealth law cannot automatically be assumed to flow from procedures under State law. In Secretary, Department of Social Security v SRA  FCA 573; (1993) 118 ALR 467, for example, the Full Court of the Federal Court held that a “pre-operative” male to female transsexual person would not be recognised as a “woman” for the purposes of Commonwealth social security legislation.
In Kevin the Court commented on the fact that State birth certificates were not “binding” on the Commonwealth as follows:
 The scheme of the Marriage Act therefore is that it relies upon and recognises State and Territory jurisdiction in the issuance of the birth certificates which are a pre-requisite to solemnisation of marriage. The Evidence Act supports the admissibility of and faith and credit to be given to the birth certificate as evidence, albeit not conclusive evidence, of the facts contained in the certificate. There may accordingly be a question as to the source of the Commonwealth’s jurisdiction, power or discretion to refuse to accept the evidence of the State certificate that Kevin is a man for the purpose of the marriage law. However, in our view the answer is that the certificate creates no more than a rebuttable presumption as to its accuracy, so that if the Attorney-General can establish that Kevin is not a man for the purposes of the Marriage Act , the presumption created by the certificate is accordingly rebutted.
It also has to be said that the decision in Kevin has never been discussed or considered by the High Court of Australia. In a case where perhaps some comment might have been expected, the appeal in NSW Registrar of Births, Deaths and Marriages v Norrie  HCA 11 involving the question whether the NSW Parliament had authorised the Registrar to enter a category of “non-specific” sex on a birth certificate, the High Court simply noted in passing that the implications of this finding may be relevant to marriage- but offered no views as to how that might be resolved; see para :
The chief, perhaps the only, case where the sex of the parties to the relationship is legally significant is marriage, as defined in the fashion found in s 5(1) of the Marriage Act 1961 (Cth) (In the Marriage of C and D (1979) 28 ALR 524; Bellinger v Bellinger  UKHL 21;  2 AC 467 at 483 .)
It is worth noting that in its final footnoted cross-references in that quote, the High Court referred to older cases denying that a transsexual person could be legally regarded as of their “reassigned” gender for the purposes of marriage, but made no comment about the decision in Kevin, which had explicitly declined to follow precisely those two earlier decisions.
On either of the above assumptions, there are serious problems for those who may be relying on Victoria’s amended law in the area of marriage. For those who are already married, either the marriage will be automatically invalidated by the issue of a new certificate, or else for the purposes of Commonwealth law the Victorian citizen with a newly issued certificate will still be regarded as being in their birth gender. For those who are single and wanting to be married in their “new” gender, it seems most likely that this will not be possible under current marriage law unless they have undergone the sort of detailed surgical processes discussed in the Kevin decision. In that case the Victorian government will be deceiving its citizens by implying that the apparent “change” with no medical procedures will be recognised for the purposes of Commonwealth law, when there is clear authority suggesting that a person who claims to have changed sex but has undergone no medical treatment to that effect, will still be regarded as being of their birth gender. For these reasons, the proposed Victorian laws seem very unwise.