Over the past decade, evangelical Christianity has increasingly defined itself by opposition to homosexuality. This movement, headed by Dr. James Dobson of Focus on the Family, relies in large part on two “scientific” assertions: First, children do better when raised by a mother and father. Second, homosexuality is a moral choice, not something one is born with — and in the minds of Dobson and Focus, it is the wrong choice. This column questions those assertions, from the perspective of an evangelical Christian who grew up listening to Dobson on the radio.

For the sake of argument, I’m going to grant that Dobson’s first claim is true, that studies indeed show that children do significantly better when they have both a mom and a dad. This assertion is controversial among scientists, but the question here is: What follows from that claim? Dobson thinks what follows is that gay and lesbian marriages should be illegal.

I disagree. First, while these studies may tell us that the children do worse, they do not tell us why. The explanation Dobson favors is that the children need both a mother and a father to develop properly. Another plausible explanation might look to the broader culture: Society is structured to support heterosexual families; homosexual families are controversial, frowned on and discriminated against; and their children are affected as a result of these patterns — which, incidentally, are cultivated and maintained by Focus.

If Dobson’s studies had been conducted in the 1800s, they probably would have found that children do much better if raised by two white parents instead of two African Americans. Of course, neither then nor now must it follow that African Americans, or homosexuals, should not be allowed to start a family.

But perhaps Dobson is right in asserting that children need the firm correction of a father and the gentle love of a mother. For now, we’ll ignore his reliance on gender stereotypes. Granting this, what follows? Should we outlaw family arrangements that don’t maximize the child’s well-being? Maybe, but we don’t do this in many other circumstances that affect the child’s well-being. While children are removed from abusive homes, they are allowed to stay with parents after a divorce, to stay with a single parent after one dies, or to be adopted by a single individual seeking to become a parent. Dobson might respond that, at least in the first two cases, the child stays in a situation that moved from ideal to non-ideal. Letting homosexuals acquire children, he might argue, intentionally introduces a child into a non-ideal situation.

Perhaps. But not letting a homosexual couple acquire a child intentionally puts that couple in a non-ideal situation. Thus, we must ask: which harm is worse? Is the child harmed more by being raised by two moms? Or is the couple harmed more by not being allowed to fulfill their desire to parent children? Reasonable people can disagree about this, and the law should allow them to do so. Additionally, it’s likely that any harm to the child would gradually decrease as society becomes more supportive of these arrangements — and organizations like Focus disappear.

What about the second claim, that homosexuality is a choice? To support this claim, Dobson cites a reputable 1991 study finding that, among identical twins raised separately, 52 percent were both homosexuals. He concludes: “if homosexuality were in the genetic code, then both individuals would have been homosexual 100 percent of the time. … This study actually provides support for environmental factors versus genetics!”

His analysis deserves a few comments. First, all behaviors and desires, and some biological conditions, are a mixture of genetic and environmental components. Type II diabetes, for example, is associated with certain genes and also results from dietary habits. Shall we conclude, then, that diabetes in not “in the genetic code”? Most doctors are inclined to say no.

Second, this study shows that non-genetic factors play a role in the development of a homosexual identity. If those factors predisposing one toward homosexuality are predominantly environmental, it still does not follow that homosexuality is a choice. Just because I was raised in Michigan and not in Florida does not mean I chose to experience annual snowfalls.

Third, while it appears that environmental, genetic and possibly choice factors contribute to homosexuality, it also appears that sexual predispositions — once formed — are relatively well established early in life. Hence the utter failure of programs designed to “de-convert” homosexuals. Hence the “ex-gay” director of Focus’s “de-conversion” program turning up in a gay bar. And hence the need for evangelicals to reconsider their stance on homosexuality.

Jonathan Dudley is a first-year student at the Divinity School and does research in molecular oncology at the School of Medicine.