The Washington Post’s Sarah Kliff and Suzy Khimm of WonkBlog discuss the shifting public opinion of gay marriage, and the reason why fiscal conservatives might want to support legalizing same-sex unions.. (The Washington Post)

After Chief Justice John G. Roberts Jr. said, “The case is submitted,” on March 27, the justices of the Supreme Court presumably took a private vote and now are at work writing the opinions that will decide the fate of same-sex marriage in the United States.

But real life doesn’t stop just because the justices have commenced their labors. And what has happened since raises the question of how events outside the Marble Palace affect the deliberations within.

Over two days in March, the justices heard separate arguments that courts should not have overturned a 2008 decision by California voters to ban same-sex marriages in that state and that it was unconstitutional for Congress in the Defense of Marriage Act to withhold federal benefits from same-sex couples who are legally married in the states where they reside.

And those challenging California’s Proposition 8 urged the court to go boldly beyond just that and declare there is a constitutional right to marry that would sweep away state bans on same-sex unions.

Since then, the remarkable turnaround in public attitude about same-sex marriage has only accelerated.

Ten senators reacted to the court’s hearings by declaring their support for same-sex marriage. That means 54 of the 100-member body, including two Republicans, favor the unions.

In the past two weeks, legislatures in three states — Rhode Island, Delaware and Minnesota — joined nine other states and the District of Columbia in legalizing same-sex marriage. A vote is likely soon in Illinois.

A Washington Post poll said that in Virginia — where in 2006 voters overwhelmingly amended the state constitution to recognize marriage as only between a man and a woman and banned civil unions — a majority now favors same-sex marriage.

Fred Sainz of the Human Rights Campaign, a gay rights group, said he feels sure the “positive momentum” won’t be lost on the court.

“It’s clear that they take into account the temperature of the American public,” he said.

No place makes a more dramatic statement than Minnesota.

“It’s got to be one of the most incredible turnarounds in political history,” said Dale Carpenter, a University of Minnesota law professor who is an expert on same-sex-marriage issues and who was active in the campaign.

After Republicans took control of the legislature, they proposed a constitutional amendment on the 2012 ballot that would ban same-sex marriage. But instead of finding an agreeable public, the move galvanized the opposition, which raised $13 million to fight the referendum measure.

Not only was it narrowly defeated, but Democrats were returned to control in the legislature. Only six months after the vote to ban same-sex marriage, Gov. Mark Dayton (D) signed a law allowing the unions.

But assuming the court is paying attention, what is the lesson? Is it that the court should feel free to act boldly, because same-sex marriage is inevitable? Or is it a sign that, as the Prop 8 proponents’ attorney Charles Cooper urged during oral arguments, the court should stay out of an ongoing political discussion?

“The question before this court is whether the Constitution puts a stop to that ongoing democratic debate and answers this question for all 50 states,” Cooper said, adding, “We would submit to you that that question is properly decided by the people themselves.”

Said Carpenter of the justices, “I think they could reason it either way.”

To that end, those who hope for a constitutional right for gays to marry could not have been heartened by recent remarks by Justice Ruth Bader Ginsburg, who they must count on for a win.

At a seminar on Roe v. Wade at the University of Chicago Law School, Ginsburg repeated her oft-stated criticisms of the decision. Although a supporter of abortion rights, she said the ruling went too far too fast and created a backlash.

“Judicial restraint” is a better alternative, Ginsburg said. “The court can put its stamp of approval on the side of change and let that change develop in the political process.”

Ginsburg never mentioned the same-sex-marriage cases, but her interviewer at the event, law professor Geoffrey R. Stone. wrote later that “the connection could not have been lost on the audience.”

The problem with that approach, according to Sainz, is that political momentum doesn’t have that much further to go.

There are 30 states with a constitutional amendment banning same-sex marriage, and overturning them would be an expensive and cumbersome process. Even if the polling is accurate about the new views of Virginians, for instance, there is no voter initiative available to change the constitution. The Republican-led legislature is unlikely to propose such a change, which requires votes in two successive legislative sessions, anytime soon.

Besides Illinois, the Human Rights Campaign sees only Nevada, New Jersey, Hawaii and Oregon as “states in play” in the next several years.

If all of those states broke in favor of same-sex marriage, and the Supreme Court reinstates unions in California, the HRC estimates that 40 percent of Americans would live in states that allow gays to marry by the end of 2016.

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