Tuesday's federal court ruling declaring Proposition 8 unconstitutional can be easily explained: There is no legitimate government interest in prohibiting same-sex marriages. It is for this reason that the Supreme Court is likely to affirm the U.S. 9th Circuit Court of Appeals and hold that the denial of marriage equality to gays and lesbians violates the U.S. Constitution.
In one sense, the 9th Circuit ruled narrowly, holding only that Proposition 8 was unconstitutional because it rescinded an existing right in the state. In another sense, though, the reasoning of the court stands for a broader proposition: The ban on marriage equality for gays and lesbians serves no legitimate government interest. Under this reasoning — though it was not the holding of the case — any law denying marriage equality would be unconstitutional.
Laws that discriminate against individuals must, at the very least, serve a legitimate government purpose. The 9th Circuit found no such compelling purpose in a California ballot initiative that rescinded the right of gays and lesbians to marry. Instead, the court concluded, the reasoning behind the law could be explained only as impermissible animus.
One contention frequently made is that marriage, by definition, is between a man and a woman. But this is not an argument; it is just a definition. Certainly marriage can be defined this way, but it also can be defined to include same-sex couples exchanging the same vows, going through the same rituals and receiving the same benefits. Nor is the long tradition of defining marriage as requiring two members of the opposite sex a reason for refusing to recognize same-sex marriages. For the first 170 years of American history, Southern states, such as Virginia, had laws prohibiting interracial marriage.
One argument made by supporters of Proposition 8 to the 9th Circuit was that marriage is inherently about procreation. But this is wrong because heterosexual couples can marry even if one or both of the partners is physically incapable of having children or if they do not wish to do so. Moreover, many same-sex couples have children, whether by adoption, surrogacy or artificial insemination.
The argument is made that children are psychologically better off with two parents of the opposite sex than with two parents of the same sex. There is no evidence to support this assertion, but it also completely misses the point. The debate is not over whether gay and lesbian couples should have children; they, of course, will do so or not for the same reasons that heterosexual couples decide whether to reproduce.
Marriage is defended as a crucial social institution because it increases the likelihood of stable relationships, which are best for raising children. Children in same-sex households thus benefit from the stability marriage provides in the same way it is thought that marriage is best for raising children when there are heterosexual parents.
Opponents of marriage equality say that allowing it will weaken the institution of marriage and thus be harmful to society. But in all the dozens of debates I've participated in about the subject, no one has ever explained in terms that made sense how allowing gays and lesbians to marry adversely affects heterosexual marriages. Allowing interracial marriages did nothing to weaken the institution of marriage and did not lead to allowing polygamy or incestuous marriages.
One central criticism of the 9th Circuit's decision is that it was wrong for the court to substitute its decision for that of the voters. However, it is a crucial judicial role to interpret the Constitution and to remedy unjust discrimination and violations of rights. It was not impermissible judicial activism when the Supreme Court invalidated laws prohibiting interracial marriage, and it is equally appropriate for courts to declare unconstitutional laws rescinding the right to same-sex marriage.
What will the Supreme Court do on this issue if it decides to review the case? Everyone on both sides of the issue expects that it will be a 5-4 decision with Justice Anthony Kennedy in the majority. In predicting his vote, it must be remembered that there have been two Supreme Court cases in history advancing rights for gays and lesbians; both were written by Kennedy. And both emphasized the absence of a legitimate government purpose for discriminating based on sexual orientation. From these opinions, it is easy to see him coming to exactly the same conclusion as the 9th Circuit: There is no legitimate interest served by rescinding the right to marriage equality in California.
No doubt many are offended by the idea of same-sex marriage. But, of course, those who don't like the idea of same-sex marriage don't have to marry someone of the same sex.
Erwin Chemerinsky is dean of the UC Irvine School of Law.