New study says gay couples really do want marriage:

One of the most significant developments in the debate about same-sex marriage is that it is gradually moving from abstract discussions about philosophy and civil rights to concrete debates about evidence and experience. As more countries and states recognize gay marriage, we learn more and more about its effects and the characteristics of the families seeking it.

Some opponents of gay marriage, like the Institute for Marriage and Public Policy (IMAPP) in a report two years ago, have argued that few gays are even interested in marriage where it's available to them. Presumably, this observation is meant to undermine the claims of SSM supporters that marriage is really needed by gay families. It also supports the notion that it's not worth running even the small risk entailed in changing marriage for the benefit of a tiny minority of a tiny minority. SSM supporters, including me, responded that the IMAPP report wasn't really an argument against gay marriage, but mostly did not challenge the underlying finding that at least initially the uptake rate had been low.

Now the UCLA's Williams Institute, which supports same-sex marriage, has taken another look at the numbers. In a new report studying the recognition of domestic partnerships, civil unions, and gay marriages across the country, the report challenges the conclusions of the skeptics that gays don't really care about marriage. The report concludes:

Data from the states that have already extended legal recognition to same-sex couples support the conclusion that same-sex couples are entering into these relationships at significant rates, with over 40% of same-sex couples already in legally recognized relationships in those states. While the proportion of legally recognized same-sex couples is still substantially smaller than the percentage of different-sex couples who are married, we predict that the rates will reach parity within the next twenty years.

In addition, the data show that same-sex couples respond to changes in how states define their relationships. For example, average monthly registrations increased in the District of Columbia when the domestic partnership rights were increased. In New Jersey, the average number of monthly civil unions was higher than the number of domestic partnerships once the expanded civil union status was made available. Conversely, when California changed domestic partnership to a status much closer to that of marriage, a large number of couples chose to dissolve their official partnerships.

The data from these states also demonstrate that same-sex couples prefer marriage over civil unions or domestic partnerships. While 37% of same-sex couples married during the first year that marriage was made available to them in Massachusetts, only 12% of same-sex couples have entered civil unions and 10% have entered domestic partnerships during the first year in which states have offered these forms of recognition. Beyond having the legal rights and obligations associated with marriage, the name "marriage" matters for same-sex couples. As a result, it may be that in states that have recently extended non-marital forms of recognition to same-sex couples, some couples are waiting to register in the hope that marriage will someday become available or recognized in their state.

What accounts for the different conclusions of the IMAPP report and the Williams Institute study? For one thing, we now have a couple more years of experience with gay marriages and partnerships to draw from. Also, while IMAPP compared the numbers of gays getting married to estimates of the total number of gays in the jurisdiction, the Williams Institute compares the number of gays getting married (or entering other formal legal relationships) to the number of same-sex couple households in the jurisdiction.

The report is full of interesting information, charts, and graphs about the characteristics of same-sex couples as compared to opposite-sex couples, including age and prior marital history, the predominance of lesbian couples among those getting married, and the similar dissolution rates for same-sex and opposite-sex couples.