The only person willing to talk was David Blankenhorn, president of the Institute for American Values. His 2007 book, "The Future of Marriage," made a serious and temperate effort to grapple with the case for same-sex marriage. Blankenhorn opposed it out of fear it would drain marriage of its central role by making it "exclusively a private relationship" that is "essentially unconnected to larger social needs and public meanings."
When I talked with him, though, he declined to predict what tangible bad things will occur in same-sex marriage states. "I disagree with those who say it will have no impact at all," Blankenhorn told me. "But beyond that, I don't think you can say."
What's equally striking is that when I made similar inquiries to people on the other side of the debate, I encountered no such reluctance. They forthrightly asserted that granting gays access to matrimony will have no discernible impact.
"I wouldn't expect much effect on the social indicators that would be visible to the naked eye," said Jonathan Rauch, a researcher at the Brookings Institution in Washington and author of the 2004 book, "Gay Marriage: Why It Is Good for Gays, Good for Straights, and Good for America." Evan Wolfson, founder of the organization Freedom to Marry, agreed: "I don't think social indicators will get worse" in same-sex marriage states.
M. V. Lee Badgett, an economist at the University of Massachusetts Amherst and author of the new book, "When Gay People Get Married: What Happens When Societies Legalize Same-Sex Marriage," was happy to answer my question. "I don't think we'll see those kinds of negative social consequences," she said. "In Europe, there's no evidence that patterns have changed for marriage, divorce or non-marital births because of same-sex marriage or registered partnerships."
In a few years, we won't have to rely on such forecasts, because the facts will be there for all to see. And they should settle the issue once and for all.
But I have a strong suspicion that both sides of the debate are right. The supporters of same-sex marriage are right in predicting that it will have no bad side effects. And the opponents are right not to make predictions.