The Supreme Court’s decision to weigh in on two gay marriage cases has raised an important question: Will the Obama administration offer clarity on whether he thinks gay and lesbian Americans have a constitutional, as opposed to a moral, right to marry?

The Obama Justice Department is not saying whether it will address this question. But sources tell me the legal team representing the plaintiffs in the Proposition 8 case — Ted Olson, David Boise, and Ted Boutrous — plan to lobby the administration to publicly declare that the right to gay marriage is protected by the constitution, and to file a legal brief supporting their argument to that effect.

This would be a big, big move on the administration’s part. And Obama must do it, for two reasons. First, because it could help influence the Supreme Court to reach a broad conclusion on the constitutionality of gay marriage. Second, weighing in could help prepare public opinion to accept this right, too.

The Supreme Court’s decision to weigh in on California’s Prop 8 may be even more important than the decision to weigh in on the Defense of Marriage Act. If the Supreme Court adopts a broad ruling that Prop 8 is unconstitutional because it violates the due process and equal protection clauses of the constitution — as opposed to a narrower ruling that can only be applied in California — that will effectively enshrine the federal constitutional right to marry, meaning it’s only a matter of time until all state statutes banning gay marriage are ruled unconstitutional.

Obama, of course, has said he personally favors gay marriage and has come out against Prop 8. But his administration has not clarified whether it sees Prop 8 as unconstitutional (as it has in the narrower DOMA case).

The prospect of the High Court upholding constitutional protection for gay marriage has already inspired some talk that such a broad reading could spark a public backlash — such as the ones that greeted Supreme Court breakthroughs against racial and gender discrimination in the 1960s and 1970s. After all, sizable numbers of Americans oppose gay marriage, and it’s illegal in dozens of states.

But my bet is that there won’t be any significant backlash to speak of this time. The circumstances are very different today. Public opinion is more favorable now towards gay marriage than it was, say, towards interracial marriage during the 1960s, when laws against it were ruled unconstitutional. Today there is far more media coverage of the Supreme Court — via the internet and cable — meaning the public will have time to grow familiar with its arguments over gay marriage, and won’t be hit out of the blue with a big SCOTUS decision.

What’s more, an American president has come out in support of gay marriage. And by the way, the backlash that was supposed to produce never materialized, either.

That said, for SCOTUS to uphold the constitutional right to gay marriage would undoubtedly be huge. And it would be helpful if Obama came out for it soon, to lay the groundwork for public acceptance of it, should the court rule that way.

Obama has not hesitated to weigh in on the High Court before. Remember how he publicly, and very bluntly, declared his view that Obamacare is constitutional? He should speak out on the constitutionality of gay marriage, too.


UPDATE: I should have been clearer on this point: Lower courts have ruled Prop 8 unconstitutional on the grounds that it violates the equal protection and due process clauses. That’s the argument the plaintiffs will make before the Supreme Court — and the one Obama should weigh in on, too.