One of the anti-gay movement’s favorite pieces of ammunition is a 2012 study by University of Texas professor Mark Regnerus purporting to find that the children of gay and lesbian people are more likely to suffer negative outcomes, including drug abuse, poor school performance, and child abuse.

As soon as Regnerus’s “New Family Structures” study was released, fellow social scientists began picking apart Regnerus’s data, pointing out that barely any of the people that he interviewed had actually been raised by same-sex couples and that he failed to control for factors like family instability. Regnerus himself has acknowledged that his study didn’t actually say anything about parenting by stable same-sex couples, but that hasn’t stopped the anti-gay right from using it to bolster its case against marriage equality…and Regnerus from providing testimony in court cases against gay marriage.

This week, the Daily Texan, the newspaper of the University of Texas at Austin, published documents it had obtained from an internal review of Regnerus’s study that found a series of methodological flaws to the research.

The findings were summed up by the dean of UT’s College of Liberal Arts, Randy Diehl, who noted that while the school wouldn’t conduct an ethics investigation into Regnerus’s work, “no policy implications about same-sex parenting should be drawn from the study”:

The post-tenure review committee met again in January of this year and was tasked by Diehl with considering only methodological problems. Based on this charge, the committee found the following, as summarized and endorsed by Diehl: “Valid methodological concerns have been raised. … A key one is this: Because the design of the study ensured that the parental same-sex relationship variable was confounded with the family structure stability variable, it is not possible to conclude that the different life outcomes between the two groups were caused by the parental relationship variable.” Diehl, citing this finding and Regnerus’ original caution that the article did not deal with same-sex marriage legal rights, agreed that “no policy implications about same-sex parenting should be drawn from the study.” But the fact is Regnerus did use those findings in court.

Specifically, UT’s review found what other critics had noted: that the Regnerus study was not about same-sex parenting, but about family instability. From Diehl’s summary:

– The design of the NFS [New Family Structures] study survey instrument guaranteed that any participant who reported that their parent participated in a same-sex romantic relationship would have also experienced some form of family instability. -Increased likelihood of negative outcomes for children who experience family instability are well-documented within existing scholarly literature.

Nobody is arguing that it isn’t difficult to find large-scale data about children raised by same-sex parents – even Regnerus has acknowledged some of his study’s shortcomings. But the problem with the Regnerus study is that the anti-gay Right continues to insist it proves a case against marriage equality – no matter how often that interpretation is debunked.