The Best Argument Against Gay Marriage

And why it fails.

How strong is the strongest argument against gay marriage?

In last week’s arguments in Perry v. Schwarzenegger, the California same-sex marriage case, it was clear that the main secular argument for limiting marriage to opposite-sex couples is the “common procreation” rationale. The idea is that marriage is properly limited to opposite-sex couples because they, and only they, can engage in procreation within their union. The lawyers defending California’s gay marriage ban, Proposition 8, did not fully elaborate the argument—the New York Times editorial page called it a “tired, and thoroughly specious, assertion.”

Now conservative blogs are celebrating—as “one of the best arguments” and “outstanding work“—the more fulsome defense of the common procreation argument made in a forthcoming article by Sherif Girgis, Robert P. George, and Ryan T. Anderson. Yet the article’s more comprehensive elaboration of the argument reveals why the Proposition 8 defenders were right not to shine too bright a light on it. Closely examined, the common-procreation argument denigrates not only same-sex couples but several kinds of married opposite-sex couples.

Princeton professor Robert George is a conservative heavyweight in debates over same-sex marriage. With two graduate student co-authors, he claims to have revealed the true nature of marriage. The article argues for common procreation as the sole basis for a “real” or “conjugal” marriage by asserting that only a man and a woman can create a “comprehensive union.” In defining that special status, the authors begin by drawing a distinction between “sexual” exclusivity and “tennis” exclusivity: “Suppose that Michael and Michelle build their relationship not on sexual exclusivity, but on tennis exclusivity. They pledge to play tennis with each other, and only with each other, until death do them part. Are they thereby married? No.” While the purpose of this distinction is initially mystifying, the authors are making a serious point. They are contending that sexual activity has been privileged over other kinds of bonding activities in determining who gets to marry.

George and his co-authors continue, however, to observe that not all sexual activity counts as a basis for marriage—what is required is sexual activity capable of producing a child. The article infers this requirement from the physical makeup of men and women. Because same-sex couples cannot create this child-producing combination by themselves, their relationship is a recreational activity more like tennis than like marriage.

But mark the sequel—if a prerequisite of marriage is procreative capacity, then are the marriages of infertile opposite-sex couples not called into question? George and his co-authors are quick to reassure with another sports analogy: “A baseball team has its characteristic structure largely because of its orientation to winning games; it involves developing and sharing one’s athletic skills in the way best suited for honorably winning. … But such development and sharing are possible and inherently valuable for teammates even when they lose their games.” In other words, infertile couples are still playing ball, even if they never win a game. They are the Phillies, except that they have no hope of ever improving.

I suspect it will be cold comfort to many infertile opposite-sex couples to hear that while their marriage is still “real,” it is a “losing” marriage as opposed to a “winning” one. Ideally, most of them view their marriages as something more than honorable defeats and would despise the contention that they had not fulfilled the central purpose of the institution. Moreover, the article says nothing of straight people who choose not to procreate. It is unclear why they would have “true marriages,” as they are not even trying to win.

George’s second argument for the centrality of common procreation to marriage is the special link that parents have to children. He and his co-authors rely on the research institution Child Trends for the proposition that “it is not simply the presence of two parents … but the presence of two biological parents that seems to support children’s development.” This source, like many cited by the opponents of same-sex marriage, does not compare the children raised by two biological parents with the children raised by two same-sex parents. Instead, the research compares children raised by two biological parents with children raised by single parents, divorced couples, and cohabiting straight couples. The study simply has nothing to do with gay adoption. And the research comparing the kids of gay adoptive parents to the kids of straight birth parents shows that the first group fares just as well as the second. On this basis, the American Psychiatric Association, the American Psychological Association, and the National Association for Social Workers all support same-sex parenting—and marriage.

From the point of view of straight couples, however, the salient aspect of the contention that two biological parents are best for a child lies in how it demeans anyone who has chosen to adopt or to use reproductive technologies (such as an egg or sperm donor) to create a family. In the view of George and his co-authors, such couples apparently are not really parents: “Children … can have only two parents—a biological mother and father.”

We all know that the common-procreation argument declares war on all same-sex marriages. But it is worth reviewing just how demeaning it is to opposite-sex couples who do not produce their own offspring. They are like losing baseball teams. They are not the real parents of their children. True, their status is not directly on the line in the gay marriage debate—George and his co-authors are not coming after their marriage licenses. But if common procreation were to be accepted as the central basis of marriage, it would necessarily treat their marriages as inferior. In its broad and unforgiving sweep, this argument is self-destructively over-inclusive. It succeeds only in diminishing the institution of marriage itself.

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