Does the Irish Constitution require same-sex marriage laws?

In an upcoming case, two plaintiffs, Katherine Zappone and Ann Louise Gilligan, will argue before the High Court that it is contrary to the Constitution of Ireland and the European Convention on Human Rights for the State not to recognise their Canadian marriage as valid for tax purposes. The question of same-sex marriage is controversial. Here - so far as are relevant - are the parts of the Constitution bearing on the State's role relating to marriage:

"Article 41
1. 1° The State recognises the Family as the natural primary and fundamental unit group of Society, and as a moral institution possessing inalienable and imprescriptible rights, antecedent and superior to all positive law.
2° The State, therefore, guarantees to protect the Family in its constitution and authority, as the necessary basis of social order and as indispensable to the welfare of the Nation and the State.
...
3. 1° The State pledges itself to guard with special care the institution of Marriage, on which the Family is founded, and to protect it against attack.
2° A Court designated by law may grant a dissolution of marriage where, but only where, it is satisfied that ­[...]"

It can thus be seen that Article 41.1 gives a pre-eminent position to "the Family", which it calls "the natural primary and fundamental unit group" of society. Article 41.3.1 pledges the State to "guard with special care the institution of Marriage, on which the Family is founded". The Irish courts have repeatedly held that these provisions of our Constitution, when speaking of marriage, envisaged only a legal union between one man and one woman. No court in this State has ever held to the contrary. So the claimants in Zappone and Gilligan v Revenue Commissiones et al. face the rather basic legal problem that the authroities are against. I would also suggest that the correct response by a court faced with this claim is to turn it down. The reasons are institutional: It is not for the court to pre-empt the legislative response (if any) to democratically made arguments for altering the long accepted understanding of the concept of marriage in our society. Long acceptance is not enough on its own to mean that a court must continue to apply a given interpretation of a constitutional provision but there is another point: In order to have the courts overturn previous decisions, a claimant must usually persuade the court in his or her case that the previous decision(s) are clearly erroneous, based on an outdated concept that offends an indisputable liberty, or something of that sort. Any judge would, it seems to me, be on somewhat tenuous ground to accept such an argument in relation to the problem currently under discussion. One avenue the court - and perhaps on appeal the Supreme Court - might take would be to adopt the approach taken in a similar case by the New York Court of Appeals just this past July in the case of Hernandez v Robles:

"We hold, in sum, that the Domestic Relations Law's limitation of marriage to opposite-sex couples is not unconstitutional. We emphasize once again that we are deciding only this constitutional question. It is not for us to say whether same-sex marriage is right or wrong. We have presented some (though not all) of the arguments against same-sex marriage because our duty to defer to the Legislature requires us to do so. We do not imply that there are no persuasive arguments on the other side -- and we know, of course, that there are very powerful emotions on both sides of the question."

The High Court of England addressed a very similar claim in a decision handed down on July 31st, Wilkinson v Kitzinger. Since 2005, the Civil Partnership Act has provided for same-sex partners to enter into legally recognised relationships. In Wilkinson, the court was asked to hold that this legal arrangement - extending something approaching marriage, but not the protection of marriage laws per se - offended against the Convention on Human Rights, or should be held to be contrary to the common law. (The petitioner, it seems, invoked the phrase "separate but equal", which was how the effect of segregation laws were somewhat euphemistically referred to in America in the first half of the 19th century and before: see para. 5 of judgment) Sir Mark Potter rejected both arguments. He said (para. 118-121):

"It is apparent that the majority of people, or at least of governments, not only in England but Europe-wide, regard marriage as an age-old institution, valued and valuable, respectable and respected, as a means not only of encouraging monogamy but also the procreation of children and their development and nurture in a family unit (or "nuclear family") in which both maternal and paternal influences are available in respect of their nurture and upbringing.
The belief that this form of relationship is the one which best encourages stability in a well regulated society is not a disreputable or outmoded notion based upon ideas of exclusivity, marginalisation, disapproval or discrimination against homosexuals or any other persons who by reason of their sexual orientation or for other reasons prefer to form a same-sex union.
If marriage, is by longstanding definition and acceptance, a formal relationship between a man and a woman, primarily (though not exclusively) with the aim of producing and rearing children as I have described it, and if that is the institution contemplated and safeguarded by Article 12, then to accord a same-sex relationship the title and status of marriage would be to fly in the face of the Convention as well as to fail to recognise physical reality.
Abiding single sex relationships are in no way inferior, nor does English law suggest that they are by according them recognition under the name of civil partnership. By passage of the CPA, United Kingdom law has moved to recognise the rights of individuals who wish to make a same sex commitment to one another. Parliament has not called partnerships between persons of the same-sex marriage, not because they are considered inferior to the institution of marriage but because, as a matter of objective fact and common understanding, as well as under the present definition of
marriage in English law, and by recognition in European jurisprudence, they are
indeed different."

For an example of a court that recently acceded to the argument to be advanced in Zappone and Gilligan, one need only look to the decision of the Constitutional Court of South Africa in Fourie v Minister of Home Affairs (December 1st, 2005). An interesting aspect of the decision is that the Court suspended the effect of its decision, thereby granting the constitutionally appropriate branch a year to pass the neccesary reform. The question of the application of international law to such a case was discussed at the time at Opinio Juris, although one must bear in mind the particular wording of the South African Constitution, as observed in the comments following the post in question. There was also, of course, in 2004 the decision of the Supreme Court of Massachusetts in Goodridge v Department of Public Health. The Court was divided 4-3, so it provides an interesting internal debate. (Cordy J.'s dissent, with whom two of his colleagues agreed, covers pp.23-46 of the pdf.)