Gay marriage statistics are hard to find. That's because the U.S. Census, the primary tracker of demographics, has never counted them. In fact, gay couples who reported as married on the 2000 census were changed to unmarried by the Census Bureau.

That will change next year. Erik Fowle reports on the San Diego News Network:

Next April, when gay couples record themselves as being married, or as unmarried partners to persons of the same sex, their original answers will be retained. The 2010 Census marks an unprecedented level of accuracy with regard to measuring the true number of same-sex couples in the United States.

The published statistics will probably increase legal protections for gay couples because they'll change from a vague demographic to a countable one. For example, politicians could better estimate the effect of allowing gay couples to adopt children.

Yet the gay marriage statistics that come from the Census next year will likely be inflated. Statisticians expect many gay couples who can't get married in their own states to report as married even if they're not. Unlike in 2000, where gay marriage wasn't offered anywhere, in 2010 couples can get married in another state. Therefore, the 2010 Census will still record them as married even if they live in a state without it.

The inflated statistics could make legislatures think that there's more married gay couples than they're actually are. However, if the statistics are inflated because unmarried couples feel it's not worth it to get married out of state, then the statistics could still reflect the overall demand for laws allowing gay marriage.

[Cross-posted at the Gay Couples Law Blog, which discusses same sex family law, estate planning, and taxes.]