For the past several Supreme Court nominations, the hot issue has been abortion. Whether a nominee supported Roe v. Wade was the litmus test, both for conservatives and liberals. Predictably, nominees shied away from opining on whether they would vote to uphold either the outcome of the case or the underlying premise that there was a constitutional right to abortion.

Abortion will not be the hot issue this time. Everyone assumes that President Obama will only choose someone he firmly believes will uphold Roe v. Wade, regardless of whether the person is willing to go on the record with that belief. Given the weakness of Republicans’ position in the Senate, there is little likelihood that Republicans would even try to stop a nominee on the abortion issue.

But there is another issue which almost certainly will come into play: Gay marriage. Unlike abortion, gay marriage has not gained wide political acceptance on a national political level (unlike “civil unions” which are gaining acceptance).

The Defense of Marriage Act was passed during the Democratic Clinton administration, and anti-gay marriage legislation has passed in many states. California Proposition 8, which enshrined the traditional definition of marriage (one man, one woman) into the California Constitution, revealed sharp ethnic and racial differences of opinion on gay marriage. Judicial decisions in Massachusetts and Iowa, and legislative authorization in Vermont, have put gay marriage on the front burner politically.

Yet gay rights in general, and gay marriage in particular, have not found an open home in the Obama administration. Notwithstanding Obama’s professed concern for gay rights, Obama has not supported gay marriage, opting for gay-marriage lite, known as civil unions.

There is no indication that Obama wants a fight over gay marriage, or wants his first Supreme Court nomination to turn on that issue. But he may not be able to avoid the issue, as much as he may like to do so.

For example, potential nominee Kathleen Sullivan submitted a brief in the California Supreme Court in support of recognizing gay marriage as a state constitutional right. The brief was submitted on behalf of numerous law professors, including potential nominee Pamela Karlan. A U.S. Supreme Court determination that gay marriage was a constitutional right would not end the debate (witness abortion) but it would spell the legal end to the Defense of Marriage Act and various state laws. While both Sullivan and Karlan are described as brilliant and worthy opponents for the conservatives on the court, it is hard to see Obama nominating either unless he is looking for a fight over gay marriage.

Elena Kagan has stated that she does not see a constitutional right to marriage, which greatly increases her chances of confirmation, but she is not without controversy on the broader issue of gay rights. While Dean of Harvard Law School, Kagan was at the center of controversy over the military’s “don’t ask, don’t tell” policy. Kagan, along with numerous other law school deans, sought to ban military recruiters from campus based on the schools’ anti-discrimination policies. Congress passed the so-called Solomon Amendment which denied federal funds to universities which did not allow military recruiting. The issue went all the way to the Supreme Court which unanimously (8-0, Justice Alito did not participate) upheld the Solomon Amendment rejected Kagan’s legal theory that the anti-discrimination policy was being applied neutrally to all potential employers and therefore did not violate the law. (The Justice Department’s recent decision not to challenge the constitutionality of the “don’t ask, don’t tell” policy, and the political hesitation to take on the issue, signals that the administration is not looking for a fight on this issue.) Nonetheless, Kagan’s stated position on gay marriage makes her more likely to be confirmed if nominated.

Other nominees certainly will be the subject of scrutiny on these issues. Some will have been on record, while others may seek refuge behind the refusal to answer questions which may come before the court. Any nominee who has come out for gay marriage constitutional rights in the past, or dares to say so during the confirmation process, likely is not confirmable.

Gay marriage may be the new abortion when it comes to the Supreme Court nomination process. But that litmus test will work only in one direction. No Democrat will have the guts to require a pro-gay marriage nominee, but many Democrats and all Republicans will disqualify a nominee on that basis.

UPDATE: Orin Hatch (R-Utah) describes his conversation with Obama, in which Obama articulated what he meant when he called for a judge who has “empathy.” The description, if accurate, seems to confirm that Obama would not nominate a gay marriage supporter:

“That’s language that only applies to real activist justices,” Hatch said. “He assured me that’s not what he meant when he talks about empathy; he is talking about a judge who has a heart but still lives with in the framework of the law,” the senator said. “That was good.”

Hatch also said Obama told him “he is pragmatic about it. He thinks most people will be happy” with his choice.

UPDATE No. 2: Richard Cohen at The Washington Post thinks the litmus test should be where the nominee stands on the New Haven firefighters’ case of reverse-discrimination and affirmative action.

UPDATE No. 3: Those calling for appointment of the first openly gay Justice, such as Sullivan or Karlan in the post above, likely will be disappointed. Not because of the sexual orientation in itelf, although undoubtedly there would be some bias against such a choice, but because of the implications for the gay marriage debate.

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