A controversial study on parenting has become a focal point of the campaign in Minnesota to pass a constitutional amendment banning gay marriage this November.

Conducted by University of Texas sociologist Mark Regnerus, the New Family Structures Study has been used by opponents of same-sex marriage to suggest that the children of same-sex couples fare poorly on a number of issues including relationships, abuse, and poverty.

But that's not what the study actually says. Regnerus' study compared children from families headed by married, heterosexual parents to children who were raised in families where one parent had a same-sex relationship at some point. The vast majority of the children whose parents had a same-sex relationship were either born out of wedlock or came from a "traditional family" that experienced a divorce. Critics say that comparison is unfair because it compares broken homes to married ones.