Why, precisely, isn't clear. As Aravosis argues, he'd be joining more than 60 national corporations, including Apple, Alcoa, Facebook, eBay, Intel and Morgan Stanley, and more than 100 Republican officials from around the country. The lawyer challenging Prop 8, Ted Olsen, has said a brief from the White House would have “great effect.” Gay rights advocates agree, and argue that there's nothing for Obama to lose in supporting the challenge.
"What's the downside? Everybody knows he is an advocate for gay marriage," said Richard Socarides, who was a special assistant to President Bill Clinton and his liaison with the gay and lesbian community. [...]One argument says that a White House brief on the issue either wouldn't have much weight with the Supreme Court, or that, as a story in the Wall Street Journal posits, that "taking such an expansive view in legal briefs could unnerve some justices in the Supreme Court's conservative wing." Additionally, the brief filed against DOMA "focuses on respecting the states' traditional authority over family law." A brief filed in the Prop 8 case would have to square that argument that the states have authority. According to the WSJ, a brief has been drafted, and now President Obama has to make the final decision to file it.
But the president has remained silent on the legal arguments over a state's authority to ban same-sex marriage, even after his declaration a year ago that—after years of "evolving"—he supports the rights of gays and lesbians to wed. In the same interview, he said the issue should be left up to the states, a position he has appeared to move away from in more recent comments.
Obama added to the anticipation in an interview last week with KGO-TV. After noting that Solicitor General Donald Verrilli, the Justice Department's top Supreme Court litigator, "is still looking into" a position on Prop. 8, he said that his personal view is that "same-sex couples should have the same rights and be treated like everybody else."
The president's words in his inaugural address, "Our journey is not complete until our gay brothers and sisters are treated like anyone else under the law," should be his ultimate guide in making that decision.