You think you’ve got a tough job? Try opposing same-sex marriage in the federal courts these days. That’s what Austin Nimocks does for a living (among other things). Nimocks is senior counsel for a conservative public-interest group called the Alliance Defending Freedom, which is devoted to protecting religious liberty. In recent years, the organization has been a principal legal defender of what it calls “traditional marriage.” Things have not been going so well lately.

Since the Supreme Court struck down the Defense of Marriage Act last June, in United States v. Windsor, fourteen courts have considered challenges to same-sex-marriage bans and related laws—and all fourteen have ruled in favor of marriage equality. Two weeks ago, the Washington Post did a summary of the first thirteen. Then a federal court in Pennsylvania joined the list. (It’s hard to keep up!) To summarize: same-sex marriage is now legal in nineteen states, which contain roughly forty-four per cent of the U.S. population. Judges in eleven other states have ruled in favor of same-sex marriage, but those decisions are stayed pending appeals.

All of this does not discourage Nimocks, who just published a report about the state of the law on marriage around the country, and a brief in the Fourth Circuit Court of Appeals arguing that Virginia’s ban on same-sex marriage should be reinstated. “We don’t worry too much about what the district courts say,” he told me. “All that matters is how the Supreme Court comes out in the end.”

Even as euphoria has enveloped many in the pro-same-sex-marriage movement in recent months, it’s important to look seriously at the arguments that Nimocks and his allies are making. The core of his approach is simple, and populist in its orientation. The rules of marriage are for the people, not unelected judges, to decide. As Nimocks writes, in his Fourth Circuit brief, “Plaintiffs, in effect, contend that the Constitution itself defines marriage as a genderless institution, and that the People have no say in deciding the weighty social, philosophical, political, and legal issues implicated by this public debate. But Plaintiffs are mistaken. The Constitution has not removed this question from the People, and it has not settled this critical social-policy issue entrusted to the States.”

Nimocks tries to turn the Windsor decision in his favor. He says that the “central theme of Windsor is the right of States to define marriage for their community”—and, implicitly, that Windsor imposes no requirement of marriage equality on the states. Also, marriage laws vary from state to state, on issues like age of eligibility; so, he argues, there is no requirement of national uniformity, either. In addition, the court in Windsor noted that the federal courts generally pay considerable deference to the states to make their own rules on marriage. In this way, Nimocks argued, the courts should defer to the people of each state to determine whether marriage should be limited to a man and a woman. Nimocks’s reading of Windsor as a states’ rights decision is plausible—and maybe his best bet—but it’s far from a sure thing. Justice Anthony Kennedy’s opinion does give several nods to the rights of states to make their own laws on marriage, but he’s clear that those laws must not discriminate.

The heart of Nimocks’s argument comes down to a single word: children. Over and over again in his sixty-page brief, he asserts that the government has a legitimate interest in favoring traditional marriage because only a man and a woman can produce children. “Marriage laws have been, and continue to be, about the pragmatic business of serving society’s child-centered purposes, like connecting children to their mother and father, and avoiding the negative outcomes often experienced by children raised outside a stable family unit led by their biological parents,” he writes. He attempts to elide the obvious response—that not all opposite-sex couples want or can have children—by saying that Virginia can presume that they will. The purpose of limiting marriage to men and women “is not to ensure that all marital unions produce children. Instead, it is to channel the presumptive procreative potential of man-woman relationships into enduring marital unions so that if any children are born, they are more likely to be raised in stable family units by both their mothers and fathers.” This, then, is Nimocks’s best response to the argument (raised by Justice Elena Kagan at the oral arguments) that marriage is about more than just having children, because lots of married people can’t or don’t have them.

There is a potentially fatal flaw in Nimocks’s child-centered argument. At the oral arguments of the Windsor case, and in the Court’s opinion, one of the Justices also seemed especially interested in children. It was Justice Kennedy, the indispensable swing vote on issues of gay rights. “There are some forty-thousand children in California that live with same-sex parents, and they want their parents to have full recognition and full status,” Kennedy said during the arguments related to Windsor’s companion case, on California’s Proposition 8. “The voice of those children is important in this case, don’t you think?” In his opinion in Windsor, Kennedy wrote that the Defense of Marriage Act “humiliates tens of thousands of children now being raised by same-sex couples. The law in question makes it even more difficult for the children to understand the integrity and closeness of their own family and its concord with other families in their community and in their daily lives.” The laws that Nimocks is defending operate in much the same way—which means that his losing streak may not end when he reaches the Supreme Court.

Photograph by Pete Marovich/Corbis.