Thomas Peters of the National Organization for Marriage (NOM) has criticized President Barack Obama for filing a Supreme Court brief in support of gay marriage.

In addition to urging the Supreme Court to strike down the Defense of Marriage Act (DOMA), the administration weighed in on a second case related to marriage equality. In a last-minute amicus brief filed in the case challenging the constitutionality of Proposition 8, California's amendment excluding gay couples from marriage, the administration argued that the amendment violates equal protection.

Appearing on the Christian Broadcasting Network, Peters said the brief would backfire on the administration.

(Related: Obama says he felt he had to act in urging Supreme Court to strike down Prop 8.)

“I think if [the brief] has any impact, it will actually have a negative one in terms of getting the result that the president wants,” Peters said. “I think he's politicized the issue. And frankly has no credibility on it either, because as that montage you just showed points out he's flipped his position several times now. … The question at the Supreme Court is whether we're going to respect the right of the 7 million Californian voters who voted to protect marriage or if the Supreme Court is going to by fiat erase their democratic vote.”

Peters also dismissed the more than 100 prominent Republicans who have also filed a legal brief urging the high court to strike down California's gay ban, saying marriage equality supporters are “trying to confuse the issue.”

“If you look at this list of Republican signers, the one thing they almost all have in common is that they are not in office anymore. They don't have to face the voters with their new marriage views. … [W]hen Republicans switch their views on marriage, they lose elections. … The Republican Party, I think, is strongly pro-marriage. It's our opponents who are trying to confuse the issue.” (The video is embedded on this page. Visit our video library for more videos.)