Writing for the majority (doesn't that have a satisfying ring to it?), Judge Robert Smith of the NY Court of Appeals — that state's highest court — offers a new argument against a right to gay marriage. Appellees had argued that the State of New York had no rational basis upon which to exclude homosexual couples from the benefits of marriage (proponents of gay marriage always argue that any such restriction is nothing more than prejudice). Judge Smith disagreed.

 

First, the Legislature could rationally decide that, for the welfare of children, it is more important to promote stability, and to avoid instability, in opposite-sex than in same-sex relationships, Heterosexual intercourse has a natural tendency to lead to the birth of children; homosexual intercourse does not. Despite the advances of science, it remains true that the vast majority of children are born as a result of a sexual relationship between a man and a woman, and the Legislature could find that this will continue to be true. The Legislature could also find that such relationships are all too often casual or temporary. It could find that an important function of marriage is to create more stability and permanence in the relationships that cause children to be born. It thus could choose to offer an inducement — in the form of marriage and its attendant benefits — to opposite-sex couples who make a solemn, long-term commitment to each other,

Nicely put. The rest of the decision is here.