“The idea that same-sex marriage is even possible is a relatively new one. Until a few decades ago, it was an accepted truth for almost everyone who ever lived, in any society in which marriage existed, that there could be marriages only between participants of different sex. A court should not lightly conclude that everyone who held this belief was irrational, ignorant or bigoted. We do not so conclude.:”

“By limiting marriage to opposite-sex couples, New York is not engaging in sex discrimination. The limitation does not put men and women in different classes, and give one class a benefit not given to the other. Women and men are treated alike – they are permitted to marry people of the opposite sex, but not people o their own sex. This is not the kind of sham equality that the (U.S.) Supreme Court confronted in Loving; the statue there, prohibiting black and white people from marrying each other, was in substance anti-black legislation. Plaintiffs do not argue here that the legislation they challenge is designed to subordinate either men or men or women to men as a class.”

“The general rule is that legislation is presumed to be valid and will be sustained if the classification drawn by the statute is rationally related to a legitimate state interest” (id. At 440) Plaintiffs argue that a classification distinguishing between opposite-sex couples and same-sex couples cannot pass rational basis scrutiny, because if the relevant State interest is the protection of children, the category of those permitted to marry – opposite-sex couples –is both underinclusive and over inclusive. We disagree.

“Plaintiffs argue that the category is underinclusive because, as we recognized above, same-sex couples, as well as opposite-sex couples, may have children. That is indeed a reason why the Legislature might rationally choose to extend marriage or its benefits to same-sex couples; but it could also, for the reasons we have explained, rationally make another coice, based on the different characteristics of opposite-sex and same-sex relationships. Our earlier discussion demonstrates that the definition of marriage to include only opposite-sex couples is not irrationally underinclusive.

:In arguing that the definition is overinclusive, plaintiffs point out that many opposite sex couples cannot have or do not want to have children. How can it be rational, they ask, to permit these couples, but not same-sex couples, to marry? The question is not a difficult one to answer. While same-sex couples and opposite-sex couples are easily distinguished, limiting marriage to opposite-sex couples likely to have children wouldrequire grossly intrusive inquiries, and arbitrary and unreliable line-drawing. A legislature that regarded marriage primarily or solely as an institution for the benefit of children could rationally find that an attempt to exclude childless opposite-sex couples from the institution would be a very bad idea.

“Rational basis scrutiny is highly indulgent towards the State’s classifications (see Heller v Doe, 509 US 312, 340-321 (1993). We conclude that permitting marriage by all opposite-sex couples does not create an irrationally over-narrow or overbroad classification. The distinction between opposite-sex and same-sex couples enacted by the Legislature does not violate the Equal Protection Clause.

“We hold, in sum, that the Domestic Relations Law’s limitation of marriage to opposite-sex couples is not unconstitutional.”

“The cases before us present no occasion for this Court to debate whether the State Legislature should, as a matter of social welfare or sound public policy, extend marriage to same-sex couples. Our role is limited to assessing whether the current statutory scheme offends the Due Process or Equal Protection Clauses of the New York constitution. Because it does not, we must affirm. Absent a constitutional violation, we may not disturb duly enacted statutes to, in effect, substitute another policy preference for that of the Legislature.

“…It would be inappropriate for us to interpret the Domestic Relations Law in a manner that virtually all conclude would not compo9rt with legislative intent. There is no basis to conclude that, when the Legislature adopted the Domestic Relations Law more than a century ago, it contemplated the possibility of same-sex marriage, much less intended to authorize it.”