Children raised by married couples do better in school, are less apt to commit crime, less likely to use and abuse drugs, and so on, than children raised by single people or by unmarried couples. Right now children being raised by gay parents have no access to these advantages. Part of the case for gay marriage rests on protecting these children's families in marriage, thereby benefitting the children themselves.

1. Gay parenting: data and existing policy

As I have noted, there are probably between 1 and 2 million kids being raised in households headed by a gay person, single or coupled. Of these 1-2 million, the Census tells us that children are being raised in at least 162,000 households headed by same-sex unmarried partners. If we assume, conservatively, that these households average 1.5 children each, that's about 250,000 kids being raised by unmarried gay partners. As I've said, even this is almost certainly an undercount of the children being raised by gay couples in the U.S.

Most often gay parents are raising their own biological children produced during a prior failed heterosexual marriage. Judith Stacey and Timothy Biblarz, "(How) Does the Sexual Orientation of Parents Matter?", 66 Amer. Sociological Rev. 159, 165 (2001). Other gay parents get kids through adoption, the process by which gay parents rescue children from the public child welfare system after heterosexual sex has produced children that their biological parents can't, won't, or shouldn't raise. More rarely still, gay parents get these kids through the use of reproductive technologies or surrogacy.

How are these kids doing, even without marriage protecting their families? The available studies on the effects of gay parenting, while not methodologically ideal, seriously undermine any argument that gays are not at least competent to raise children (the "competence argument"). While the studies may not yet prove that gay couples are just as good as heterosexual couples at raising children (the "optimality argument"), they point strongly to the conclusion that gays are at least fit parents.

William Meezan and Jonathan Rauch, who support same-sex marriage, recently reviewed most of the literature on same-sex parenting, including more than 50 studies, many literature reviews, and dissertations and conference papers dating back to the 1970s. William Meezan and Jonathan Rauch, "Gay Marriage, Same-Sex Parenting, and America's Children," 15 The Future of Children 97, 100 (2005) (available at http://www.futureofchildren.org/information2826/information_show.htm?doc_id=290831). There are methodological problems with many of the gay-parenting studies, as Meezan and Rauch acknowledge. These problems have to do with things like small sample sizes, non-representative samples, and the like. But Meezan and Rauch looked, in particular, at four recent studies with sound methodologies, including large and representative samples, and one which looked at long-term effects. The recent studies reached the same conclusions as the previous studies on the issue.

Three conclusions from their review of the data and studies are most relevant to this debate: (1) lesbian and gay parents are very similar to heterosexual parents; (2) children of gay parents are no more likely to be confused about their gender identity or to be homosexual; and (3) children of gay parents "show no differences in cognitive abilities, behavior, general emotional development, or such specific areas of emotional development as self-esteem, depression, or anxiety." Meezan and Rauch, at 103. In fact, as Meezan and Rauch note, in some ways children raised by gay parents do better than the children raised by heterosexual couples. This is probably partly a consequence of the fact that for many gay couples having and raising children is a careful and deliberate choice for which they have prepared themselves financially and otherwise over a long time period; "oops" babies are not a phenomenon common to gay life.

While more work must be done to shore up these conclusions, a strong provisional judgment can be made that gay people are at least competent -- not unfit -- to raise children.

But don't take my word for it or the word of these researchers: It is the policy judgment of all 50 states that gays are competent to raise children. In no state are gays categorically prohibited from raising kids. In 49 states gays may adopt children. (In only one state, Florida, are gays prohibited by statute from adopting children and even there gays are allowed to serve as long-term foster parents.) In many jurisdictions, the unmarried partner of a child's parent may become the legal "second-parent" of the child. In child-custody disputes between divorcing biological parents, one parent's homosexuality is never a categorical bar to custody and is increasingly not even viewed as relevant per se to the custody decision. Gays may also use reproductive technology to procreate kids and may enter surrogacy arrangements, just as straight couples may.

The national public-policy verdict is in and it is decisively in favor of gay parenting. The argument that gays are not competent to raise children has no factual basis, no support in the research, and no support in public policy anywhere in the country.

Then there's the optimality argument. We don't know how married same-sex couples would compare to married opposite-sex couples in raising children because we haven't had gay marriage anywhere until very recently. Comparisons between straight married couples and unmarried gay couples to prove the optimality argument are off the mark, and premature. Many people have a powerful intuition that, all else being equal, an opposite-sex couple would be better at child-raising than a same-sex couple. It's a reasonable proposition, and it may be correct, but there's no direct evidence for it. The studies on the effects of fatherlessness are not evidence for the optimality argument, since these studies largely compare married couples to single parents and reach the rather obvious conclusion that two married parents do better on average than one single mother. And of course none of this fatherlessness literature compares gay couples to straight couples. Maybe opposite-sex couples are generally better than same-sex couples at raising kids, maybe they aren't. We don't know. But as I will now argue, it doesn't really matter to the debate on gay marriage.

2. Children and the gay-marriage debate

Even if we conceded what most people assume -- that opposite-sex married households are the best environment for raising children, and in particular would be better than married same-sex households — that's no argument against gay marriage. Gay marriage won't take children away from mothers and fathers who want to raise their children together.

No responsible opponent of gay marriage advocates removing all children from the care of gay parents. I suppose that could be proposed and we could debate it, but such an unimaginably cruel and destabilizing policy is not even on the table. So whether or not gay marriage is allowed, children will continue to be raised by gay parents in very large absolute numbers.

The only real question is, will these 1-2 million children be raised in homes that are eligible for the protections and benefits of marriage or will they not be? If it's better for children to be raised by married opposite-sex couples than by unmarried opposite-sex couples (as the evidence shows it is), it would surely be better for children to be raised by married same-sex couples than by unmarried same-sex couples. The marriage of their parents will have some effect and it won't be to make them worse off. For purposes of the gay-marriage debate, that's the relevant comparison, not the comparison between existing married opposite-sex couples and hypothetical married same-sex couples.

I suppose the optimality argument would be relevant if gay marriage would encourage gays to procreate children, through reproductive technologies and surrogacy, that they would not procreate in the absence of marriage. Given the expense and uncertainty involved, the numbers of people who use these methods are so small that any such effect would be trivial. Any disadvantage from the optimality perspective would, in any event, likely be overwhelmed by the advantages given (1) to the much larger number of children already living in gay families and (2) to the children such families will continue to raise in the future through the more common routes I've listed.

Gay marriage might also increase the number of children gay families adopt. But given that there's no shortage of children who need adoptive parents, and given that child-welfare experts agree that adoption is far preferable to foster care, any increase in adoptions should be seen as a benefit -- not a harm -- of gay marriage.

Further, while everyone assumes that gay marriage will mean more gay parenting, the opposite might well occur. Many gay parents are raising children from heterosexual marriages they entered in the hope of escaping their own shame or the consequences of anti-gay stigma. To the extent gay marriage reduces that shame and stigma over time, we should expect to see fewer gays entering such marriages and producing children through them, children that will have to undergo the pain and dislocation of divorce. Stacey and Biblarz, at 165.

Traditionalists are rightly concerned about the stability of home life for children. Gay marriage, in many conceivable ways, should lead to greater stability in hundreds of thousands of homes raising children in this country. The result should be that, to some extent, these children will do better in school, be less likely to commit crime, be less likely to use and abuse drugs, and so on, than they would be if we continue to keep their parents from marrying. If it's really a concern for children that's motivating opponents of gay marriage, they should be pounding the table for gay marriage as a way to protect millions of children.