Rejecting the due process and equal protection arguments for heightened scrutiny, the New York Court of Appeals in its important decision last week applied rational basis review to the exclusion of gay couples from marriage. This should have been an easy route to denying the plaintiffs' claims.

As ordinarily applied, rational basis is a very forgiving standard. The law must be (1) rationally related to (2) a legitimate end of the state. The law need not be very wise or very good to survive. As I once heard Richard Epstein memorably describe it, the rational basis standard basically asks whether any fool could come up with a stupid reason for a bad policy.

The New York court offered two rationales to meet this undemanding standard, both of which had to do with children.

"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." (p. 5) Children need permanence and stability in their lives. Yet the heterosexual relationships that produce them, said the court, "are all too often casual or temporary." Homosexual couples do not become parents by "accident or impulse"; they must plan ahead and obtain children through adoption, artificial insemination, or some other "technological marvels." Unstable relationships among heterosexuals therefore "present a greater danger that children will be born into or grow up in unstable homes than is the case with same-sex couples."

Note the irony of this argument. For decades, homosexual life has been medicalized and pathologized by doctors, sexologists, psychiatrists, and politicians. Only 33 years ago, homosexual orientation was still officially a "disorder." Gays, especially gay men, were denounced as hopelessly promiscuous, unstable, histrionic, and self-absorbed. Above all, this medico-political consensus held, homosexuals were dangerous to children and should be kept away from them. From the outset of the gay-marriage movement, a vocal opposition argued that the supposedly innate instability of homosexual relationships disqualified them from marriage.

Now, in the most important judicial decision yet rejecting a claim for gay marriage, we are told that gay couples may be kept from marriage not because they are unstable, but because heterosexual couples are unstable. Implicit in this view is that gay couples don't have as large a need for the "inducement" to "make a solemn, long-term commitment to each other." (p. 6) Implicit also is that gay couples are likely to plan more responsibly for the upbringing of their children. We thus have less reason to worry about the children gay couples are raising. Is the New York legislature listening?

The court is not saying that gay couples are more stable than heterosexual ones. It is saying that the social cost of heterosexual instability is much greater because of the toll it takes on children. And this much seems right. Sexual irresponsibility among heterosexuals imposes huge costs on our society. One-third of children are now born out-of-wedlock. Unwanted pregnancies lead to abortions. Unwanted and uncared-for children are more prone to violence, crime, drug use, ill-health, and so on.

What the New York court has done, then, is give us a very good reason why heterosexual couples should be permitted to marry. Their children badly need them to have the "inducement" marriage provides for the formation of long-term commitments. Otherwise, heterosexuals are too likely to abandon their responsibilities. There is no doubt the state has a "legitimate interest" in the institution we call marriage.

But how is the exclusion of gay couples "rationally related" to this legitimate interest? How does excluding them and their children from the stabilizing influence of marriage help families headed by heterosexuals? How does denying marriage to gay families make heterosexual ones more stable, long-term, and committed? The anti-gay-marriage movement has been trying for more than a decade now to answer these questions, to offer a believable theory of harm.

Whether you think anti-gay-marriage activists have done so convincingly is beside my point here. The point is that the New York court never even tries to answer these questions. The court simply has no explanation, rational or otherwise, for why heterosexual happiness in marriage depends on homosexual exclusion from it. You could come up with such a tale, but the New York court does not do so. The omission is striking.

The New York court offered a second rational basis for excluding gay couples from marriage. "The Legislature could rationally believe that it is better, other things being equal, for children to grow up with both a mother and a father." (p. 6) In response to social-science studies cited by the plaintiffs concluding that there are no differences between same-sex and opposite-sex couples in raising children, the court argued that the studies did not conclusively establish that the legislature was irrational to prefer heterosexual parents.

I agree with the court that the social-science studies on parenting, to date, do not establish conclusively that children do as well in same-sex households as in opposite-sex ones. The day may come when it would indeed be irrational to doubt this. We're not there yet.

But once again the key question left unanswered by the court is, how does the exclusion of gay couples from marriage rationally advance the putative preference for heterosexual couples in child-raising? If we were faced with a choice between awarding a child either to a heterosexual or homosexual couple then, all else being equal, it would be rational for the legislature to prefer the former, given the present state of our knowledge. A policy that gave a preference in such cases to heterosexual parents would rationally promote the state's interests.

But that is not what's at stake in the question of whether gay couples should be able to marry. If the state could rationally claim that gay couples are incompetent to raise children, that would be one thing. Neither New York nor any other state takes that position, since all states permit gay people to raise children (some, with restrictions and qualifications). In New York, it is possible for a same-sex couple to adopt a child, but not to protect their joint responsibility for that child with marriage. New York guarantees these children will be raised outside of marriage. You could, I think, come up with some explanation for how excluding gay couples promotes what the state regards as the optimal familial arrangement, but the New York court's analysis of this point is missing.

Let me be clear: I am not saying that existing marriage laws can't satisfy rational basis review. It would be surprising if they couldn't satisfy it, notwithstanding the conclusion of the majority of the Massachusetts high court in Goodridge. In fact, the best example of the application of rational basis to uphold the exclusion of gays from marriage is still Justice Cordy's dissent in that case. His opinion is at once respectful of homosexuals' claims, temperate in tone, closely reasoned, and a model of the kind of judicial humility associated with the test. By contrast, the New York decision is remarkably thin.

UPDATE: A number of the comments seem focused on filling in arguments the majority could have made on rational basis review (e.g., that marriage includes those couples, and only those couples, that present the problem the state identifies). I have no quarrel with these efforts. The point of the post, however, is that the New York court surprisingly omits these sorts of easy steps in the analysis. It identifies the legitimate end and then stops.

It's worth asking why the court's argument is incomplete. I can only speculate, but I'm guessing it's because the court is reluctant to flesh out in too much detail a very narrow normative vision of marriage that hardly anyone -- outside a few doctrinaire anti-gay-marriage activists -- seems to believe. In order to defend traditional marriage using these types of arguments we have to diminish it as an institution and to demean many existing marriages. That's not a legal problem for judges applying rational-basis review, but it is a cultural problem for anti-gay-marriage activists and for judges who want to be seen as making persuasive arguments, not just minimally rational ones.