By Prof. J. Stephen Clark

The fight over same-sex marriage is over, right? The Supreme Court certainly left that impression last year after Obergefell v. Hodges, when it vindicated the constitutional right of gay couples to get married. A recent decision out of Mississippi, however, highlights a possible vulnerability for lawfully married same-sex spouses. What, if anything, obliges a state to give them the same benefits that generally flow from marriage?

The problem with the Mississippi decision was not the result, but the reasoning. A federal judge there struck down a state law that prohibited joint adoptions by married couples of the same sex. Despite noting that the state made only a “tepid” effort at defending the ban, the court gave only a feeble rationale for enjoining it. Equal protection was somehow involved.

The judge got the general framework right. If a law does not target a protected class or infringe a fundamental right, it should be upheld as long as it survives mere rational basis review. But from there, incoherence followed. The judge did not hold that the law targeted a protected class or that it infringed a fundamental right, but he struck it down anyway and did so without applying any standard of review. His rationale? Doubt that the Court would uphold the ban. Fair enough, but a more certain basis would be nice.

The judge’s difficulty in articulating one was understandable. The adoption ban inspired four possible theories of invalidity, but none of them quite encompassed it. The ban lay in a constitutional gap, which the Court itself is responsible for maintaining.

First, by singling out same-sex couples, the ban on joint adoptions might have targeted a protected class and thus triggered heightened scrutiny on that basis. The Court, however, has repeatedly avoided holding that classifications based on sexual orientation trigger heightened scrutiny. Nor has it been willing to treat discrimination against same-sex couples as a gender-based classification, which also would trigger heightened scrutiny. Even while repeatedly invalidating anti-gay laws, the Court has preferred to remain coy as to the standard of review—for two decades now. Given the absence of evidence that same-sex couples make bad parents, the adoption ban would almost certainly have failed heightened scrutiny.

Second, by denying some couples the opportunity for a joint adoption, the law might have infringed a fundamental right to adopt. As important as adoption may be to infertile couples and others, however, the Court has never held that adoption is a fundamental right. It is a statutory creation of relatively recent vintage and thus lacks a long history and tradition, a weighty factor in identifying a fundamental right. Adoption also implicates the private interests of additional parties—namely, the children placed for adoption and their biological parents. Perhaps understandably, courts have generally declined to require states to defend adoption regulations under heightened scrutiny.

Third, by denying same-sex spouses a marital benefit that heterosexual spouses receive, the law might have infringed the fundamental right to marry. That right has been defined, however, as protecting individuals from material interference with their decision to get married, not as a constitutional entitlement to receive any particular set of benefits once they do. In fact, unremarkable socioeconomic regulations sometimes extend marital benefits to only some spouses, such as those who actually live together, those over a certain age, or those in specified economic circumstances. Several states even offer married couples the option of a “covenant” marriage, which significantly alters the availability of divorce. The Court has never suggested that varying the marital benefits available to different married couples, standing alone, triggers any heightened scrutiny. Although the judge in the Mississippi case tried to derive a countervailing principle from the Obergefell decision, which did rest on the constitutional right to marry, the issue of denying a marital benefit to a subset of lawfully married couples was not before the Court. The right to get married was.

Fourth, the adoption ban might have just failed rational basis review without any heightened scrutiny. Because that standard of review is so toothless, however, a claim that the ban serves the best interests of children should survive that minimal scrutiny. Although studies consistently find little to no difference in outcomes between children raised by same-sex and heterosexual couples, the experience is recent and the studies are somewhat limited. As the New York Court of Appeals has held, a rational legislator could doubt the studies’ conclusiveness. Applying an adoption ban to all same-sex couples would be blunt and imprecise. No one seriously claims that the best same-sex parents are still worse than the worst heterosexual parents, but rational basis review does not require such neat categorical difference. It allows gross overinclusion and gross underinclusion, as long as there is some conceivable basis for the line that is drawn. It should be enough that a rational legislator could imagine a hypothetical statistical difference that might correlate with the classification. Yes, rational basis review is that toothless.

On occasion, the Court has applied it with more “bite” than usual. At least twice, in fact, it has done so in striking down laws that discriminate against gays and lesbians or same-sex couples. The best example is the case of Edie Windsor, in which the Court invalidated the provision of the federal Defense of Marriage Act (DOMA) that required the exclusion of lawful same-sex spouses from all marital benefits under federal law. There, however, the Court stressed the breathtaking sweep of the discrimination and identified clear examples of anti-gay animus in the legislative history. Although one might well find anti-gay animus infecting the enactment of the Mississippi ban, a law withholding one specific benefit of marriage in an area with colorable social science uncertainty is quite different from the totalizing sweep of DOMA. In other instances, even the evidence of legislative animus may be much harder to come by than in the case of DOMA (or Mississippi). This possibility of situationally intensified rational basis review is a shaky security for the full and equal availability of marital benefits.

None of these problems, moreover, is limited to the denial of adoption rights. A law that withholds any kind of marital benefit from same-sex spouses would implicate the Court’s unwillingness to formally elevate the standard of review for classifications based on sexual orientation. In contrast to adoption, moreover, few other marital benefits—think survivor benefits, tenancy in the entirety, or testimonial privileges—could even plausibly qualify as fundamental rights. In addition, the focus of the constitutional right to marry on getting married, as opposed to receiving benefits, would also arise as a problem regardless which marital benefit were withheld. Lastly, the toothless nature of rational basis review would be a problem in many instances, as surviving it merely requires a clever lawyer for the government to postulate some plausible and conceivably relevant demographic difference between same-sex and heterosexual couples, such as potential differences in rates of actual dependency between spouses.

If one believes that result of the Mississippi decision was correct and that states should have only limited discretion to withhold particular marital benefits from lawfully married same-sex couples, the best solution for filling the constitutional gap and bringing coherence to the question lies with the first of the four legal theories. The probability is sufficiently great that a law targeting gays and lesbians or same-sex couples is motivated at least in part by prejudice to justify the Court in presuming unconstitutionality in all such instances and thus requiring a state to disprove it by surmounting a higher standard of review than the toothless rational basis test. Elevating the standard of review for such classifications addresses the essence of the problem without generally requiring the recasting of all marital benefits as fundamental rights or establishing heightened scrutiny for every socioeconomic regulation that varies the benefits offered to different married couples.

The Court should stop being coy about its basis for striking down anti-gay laws. It should finally acknowledge that laws classifying on the basis of sexual orientation come before the courts with the same presumption of invalidity as laws classifying on the basis of other suspicious traits. There are so few remaining instances of classifications based on sexual orientation in the law that the risk of unanticipated consequences is negligible. But the benefit to doctrinal clarity would be significant.