Although it was not their intention, National Organization for Marriage has posted a graph that proves that falling marriage rates in the United States cannot have been caused by the legalization of same-sex marriage.

Despite NOM’s claim in the graph’s caption that “Marriage rates down, out-of-wedlock birth rates up. Conservatives may have correctly predicted the consequences of same-sex marriage,” the graph clearly shows that the marriage rate has been falling steadily since at least the 1960s, well before same-sex marriage first became legal in Massachusetts in 2004.

I added a red arrow to NOM’s graph to mark the date that same-sex marriage became legal in Massachusetts. It clearly happened at the end of a 50-year period of decreasing heterosexual marriage rates and therefore could not have caused the decline.

Thank you, NOM, for proving that the legalization of same-sex marriage cannot possibly be the cause of decreasing marriage rates.