NEW YORK (MainStreet) — Tuesday the Supreme Court heard arguments in Obergefell v. Hodges, challenging the constitutionality of same-sex marriage bans. Gay rights advocates have launched a series of successful legal challenges to bans across the country in the wake of the Court's decision in United States v. Windsor, using the federal courts to establish a right to marry in 21 states.

Gay-rights advocates expect to continue that victory at the Supreme Court this term relying largely on language written by swing vote Justice Anthony Kennedy in Windsor, and have good cause for optimism. 

Opponents of gay marriage have increasingly struggled to come up with effective arguments to support their cases in court, largely because their traditional position that gay marriage can be banned on the grounds of faith and morality has no place in American law. Even hardened opponent of the issue Justice Antonin Scalia pointed that out in his dissent to Lawrence v. Texas, writing of laws against same-sex marriage that “[i]f, as the Court asserts, the promotion of majoritarian sexual morality is not even a legitimate state interest, none of the above-mentioned laws can survive rational-basis review.”

Without credible evidence that gay marriage harms children or weakens marriage for the heterosexuals, the defense on Tuesday was reduced to its Hail Mary argument: that legal marriage is all about procreation and “keeping the couple bound to that child forever.”

It’s a vision of marriage that would be embraced by Barney Stinson, Neil Patrick Harris's character on "How I Met Your Mother" -- a scenario where utterly exhausted couples who would otherwise abandon spouse and child for a freewheeling life of adventurous sex stick around for the sake of the tax breaks. In the telling of John Bursch, who argued for the state of Michigan, they also continue to have dutiful, patriotic intercourse without protection.

That is, after all, why they got married.

Only a jurist desperate to hang his hat on any reason for banning gay marriage could embrace this tortured logic. Fortunately for Bursch, he already happens to have three or four of them waiting at the Supreme Court. Justices Clarence Thomas, Antonin Scalia, Samuel “What if they were siblings?” Alito and most likely Chief Justice John Roberts will vote in favor of the states. Kennedy -- by gracious assent of his colleagues, the closest thing America has had to a king since George III -- is the swing vote. Most court watchers have him pegged as a plaintiff’s vote.

But what if he’s not? Especially for a judge with a deep love of federalism like Kennedy, there will be a lot of appeal to letting the states continue sorting this out. If that happens, it will roll back the decisions in 21 states expanding the right to marry.

America has a long history of enforcing and expanding court-made rights, but not much figuring out how to take them back. With defeat for gay marriage proponents a very real possibility before the court, now is the time to start wondering, what happens if the court says no?

Plan A: The Court Rules Against Gay Marriage

According to Professor Richard Friedman at the University of Michigan Law School, the 21 states affected by federal court decisions over the past few years would be free to ban gay marriage again virtually immediately. In fact, in many, if not most of those states, the bans may still be on the books and would snap back into place as soon as the Court handed down its decision.

“Presumably,” he said, “if it’s a dead loss for the plaintiffs it would undo those decisions. I say presumably, because there may be other issues, and those states would be free to decline to license any further same sex marriages.”

Professor William Baude, with the University of Chicago Law School agreed, saying that to him it is “relatively clear that states would be able to go back to their old ways.” The ones that banned same sex marriage before an intervening federal ruling could pick up where they left off, although several would probably decide to enact legislation addressing the issue on their own.

The more complicated question, however, is what happens to the marriage licenses already handed out.

“There would be a good deal of confusion,” Friedman said. “It would create a good deal of short term turmoil if the political officers in those states declined to recognize the marriages that had already been entered into.”

Lawyers call it revocation, and when it comes to civil rights, no one really knows how it works. According to Baude, the Supreme Court’s jurisprudence offers no clear way forward, just more questions. Legal scholars in general agree and disagree on every possible outcome. Some argue that marriage licenses already handed out would remain valid, while others urge that a Supreme Court decision would apply retroactively, holding that the lower courts were wrong in ever ruling that a right existed. Many say it would be up to the individual states.

In other words, for thousands and thousands of people already married, no one knows. The courts have no clear guidance for the inevitable tidal wave of litigation that would ensue, which would very likely end up back at the Supreme Court.

It’s not an academic question either. Marriage confers hundreds of benefits at the state level and well over a thousand from the federal government. Unwinding all of these simultaneously would be immensely complicated, if even possible. Perhaps most challenging of all would be resolving past decisions made based on a now-invalidated status, such as tax returns and insurance payments. In the wake of a decision announcing that all of these couples have become newly-unmarried, potentially years or decisions would be retroactively voided.

More certain would be the political fallout. Friedman compared it to the right’s galvanizing moment in Roe v. Wade.

“I’ve often said that the best thing for the pro-life movement was Roe v. Wade, in that it energized the pro-life movement and generated a lot of money,” he said. “I think the same thing might be true here, in that a dead loss for the advocates of same-sex marriage would mean enormous potential fundraising and an enormous political benefit.”

In fact many states would likely prove effective grounds for political action, as in the wake of court decisions of the past several years they’ve been content to allow the process to happen judicially.

However there’s a hard limit to how far activism on the issue of gay rights can go, and many staunchly conservative states remain firmly opposed to allowing gay marriage at any political price. These states draw comparisons among the supporters to Loving v. Virginia, which legalized interracial marriage. Like with Loving a ruling is necessary, these states argue, because some states simply will never see this happen at the ballot box.

Recognition in the States

The Court could instead split the difference, declining to protect a Constitutional right to gay marriage but requiring states to recognize the couples from states that do.

“It is possible to have an equality argument about recognition that doesn’t go all the way,” Baude said. “The Court could, I’m not sure they’re going to do this, but the Court could say that states are required to recognize marriages from out of state as a matter of equality even if they’re not required to do it themselves.”

It would be a decision steeped in exactly the sort of federalism that Kennedy is known to love, and would allow the court to in some ways have its cake and eat it too, giving gay marriage activists something without wading entirely into the culture war. It would also be legally consistent. Full faith and credit, as a principle, is about local governments respecting out of state decisions that they would not have made themselves.

It would at the same time create a whole new kind of problem, transforming gay marriage into a class issue.

Keeping this a state-by-state issue creates a logistical nightmare for couples, who as often as not have to choose their residence based on their rights. Joint assets or decision-making authority enjoyed in Illinois dissolve upon crossing the border into Michigan.

Yet a recognition diaspora might almost be just as bad, reserving marriage in many states for the gay couples wealthy enough to travel for it. It would grant almost nothing to the states in opposition, since they would have to recognize the marriages of the overwhelming majority of gay citizens. Instead, the issue would boil down to symbolic resistance at the expense of the most vulnerable.

And lest anyone say that never happens…

Don’t Pop the Champagne Yet.

But keep it chilled. The biggest consequence of a negative ruling would simply be widespread uncertainty, particularly about the status of married couples. It would be new territory and for that reason alone is an unlikely result. The Supreme Court tends to avoid decisions that will unleash chaos. Both Friedman and Baude agreed that to them, this is the issue that most effectively convinces them of how the Court will vote on gay rights.

After the Court lifted its stay on issuing new marriage licenses in states affected by federal decisions, Friedman said, it would be “very unusual” for it to go back and plunge those same states into chaos.

For now, couples should proceed cautiously. Assets and power of attorney should be arranged as though the partners are unwed and likely to stay that way, or couples should arrange their affairs in states where gay marriage came about through state-level resources.

There’ll be no harm done if this June the justices hand gay marriage advocates a nationwide win, but there’s no sense in courting uncertainty if they decide to say “we don’t.”

One Last Clarification 

First of all, let's dispose of one rumor persistent in the same-sex marriage debate: Chief Justice John Roberts is not concerned with the partisan image of the Supreme Court.

It's just not true.

Sorry to play Snopes for a lot of very smart people, but beyond the Chief Justice's own propaganda, there is no reason to believe that he has a problem with highly polarized, 5-4 decisions.

Yes, Roberts repeats often his profound concern for the image of the Supreme Court, and yes, it's increasingly odd that he has allowed this to become Anthony Kennedy's Court, effectively. We have to judge by his record though, and the Chief Justice has an eight and a half year career of near rock-solid party-line voting on every ideologically charged issue aside from Obamacare, the exception that proves the rule

-Written for MainStreet by Eric Reed, a freelance journalist who writes frequently on the subjects of career and travel. You can read more of his work at his website A Wandering Lawyer.