Supporters of same-sex marriages gather outside the US Supreme Court waiting for its decision on April 28, 2014 in Washington, D.C.
Photo by Mladen Antonov/AFP/Getty

What if gay marriage loses?

For months, legal experts and LGBT advocates have been talking about nationwide marriage equality as an all but foregone conclusion. The country is, after all, well over halfway there already, with same-sex couples able to wed in 36 states, the District of Columbia and parts of Missouri. Additionally, the high court – which will soon decide whether the Constitution requires states to license and/or recognize same-sex nuptials – has in the past year allowed marriage equality to go forward in over a dozen states either by denying requests to hear appeals, or by refusing to grant emergency stays in cases where federal courts have struck down same-sex marriage bans.

Andrea Mitchell Reports, 4/30/15, 12:35 PM ET

Same-sex couples optimistic as SCOTUS weighs marriage ruling

Sandy Stier and Kris Perry, plaintiffs in the Supreme Court case that ended California’s ban on same-sex marriage in 2013, join Andrea Mitchell to talk about the cases argued this week, and what the Justices’ ruling would mean for the country.
On Tuesday, the justices appeared closely divided during oral argument in Obergefell v. Hodges, an historic case that could invalidate the country’s remaining 14 same-sex marriage bans. While LGBT advocates remain confident they’ll secure a win come June, tough questions from likely swing vote Justice Anthony Kennedy left some wondering, ‘What if they don’t?’

In short, the answer to that question is that complete chaos would follow – perhaps so much chaos as to whittle down the chances of the ruling actually going that way to a virtual impossibility.

“One of the things driving the Supreme Court for a 50-state solution is the administrative nightmare that would follow if it did something short of that,” Kenji Yoshino, constitutional law professor and author of “Speak Now: Marriage Equality on Trial,” told msnbc.

If the high court rules against same-sex nuptials in this case, the decision wouldn’t just keep alive the four bans currently under consideration in Kentucky, Michigan, Ohio, and Tennessee; it would clear a path for lawmakers in 20 other states to resurrect same-sex marriage bans that were struck down by federal courts. Those states would, however, likely still have to go on recognizing the thousands of same-sex marriages that took place during the period in which they were legal. Meanwhile, gay and lesbian couples would continue to be able to marry in 16 states where such unions were adopted by the legislature, popular vote, or by a decision of the state court.

RELATED: SCOTUS hears historic marriage equality case

So essentially, a loss for same-sex couples in June would exacerbate the patchwork system of laws currently causing marriages to “fade in and out like a radio signal,” as Yoshino put it, depending on where in the country a couple lives or travels through. And because some states would be able to reimpose their bans while still having to recognize same-sex marriages legally performed over the past several months, the validity of thousands of marriages would end up hinging on when those couples were wed, as much as where.

Add in the existing disparity between federal and state recognition of same-sex unions, and the end result of a loss for marriage equality this summer is nothing short of a total legal mess.

Not that the country hasn’t dealt with such messes before, albeit on a smaller scale. Back in May of 2008, California’s Supreme Court overturned the state’s statutory bar to same-sex nuptials, clearing the way for gay and lesbian couples to begin marrying there. That November, however, California voters enacted Proposition 8 – the state’s former constitutional ban on same-sex marriage – which threw into uncertainty the statuses of 18,000 same-sex marriages that took place during the five months when they were allowed.

The state Supreme Court in 2009 stepped in and declared those marriages valid. Prop 8, the court found, could not be applied retroactively, but could prohibit gay and lesbian couples from marrying in the future. Later that year, California’s then-Gov. Arnold Schwarzenegger signed into law a measure requiring the state to recognize same-sex marriages performed in other states between June and November, 2008, in addition to in-state same-sex marriages licensed during that time.

RELATED: Prop 8’s impact on marriage equality

Yet the marriage situation in California remained, as attorney Ted Olson argued in his challenge to Prop 8, “an utterly irrational regime” that created four separate classes of citizens: opposite-sex couples who could marry; same-sex couples who could marry in 2008 but couldn’t remarry after 2008; same-sex couples married outside of California in 2008, whose marriage were considered valid inside of California; and all other same-sex couples prohibited from marrying by Prop 8. Uniformity in marriage was not returned to California until the Supreme Court allowed Prop 8 to fall in 2013.

Similar cases have since occurred in Utah and Michigan, where same-sex couples were able to marry for brief periods after federal judges struck down the states’ same-sex marriage bans and did not stay the effects of their rulings. Higher courts later put a stop to the practice, leaving hundreds of same-sex marriages in legal limbo. But in both states, judges ended up declaring those marriages legally valid.

“[W]hat the state has joined together, it may not put asunder,” wrote U.S. District Judge Mark A. Goldsmith, a President Obama appointee, in a January ruling requiring the state of Michigan to recognize nearly 300 same-sex marriages performed during the brief period in which they were legal. Law experts are confident the same logic would apply in the event that the U.S. Supreme Court clears the way for states to reimpose their same-sex marriage bans.

“Once you get married, you’re married,” James Esseks, director of the ACLU Lesbian Gay Bisexual Transgender & AIDS Project, told msnbc. “Even if there’s a court decision that says maybe it shouldn’t have happened … it doesn’t change the reality that the state did issue licenses and they’re married. That’s what we think would happen to the people who are already married if the plaintiffs were to lose in Obergefell.

WATCH: Justices divided in same-sex marriage case

Of course, Esseks continued, there’s little to suggest that the plaintiffs would actually lose Obergefell based on oral argument this week. Yes, Justice Kennedy did express concern about changing the definition of marriage that “has been with us for millennia.” But he also acknowledged that same-sex couples might want to marry to show that they, too, “have a dignity that can be fulfilled.” Chief Justice John Roberts, whose vote is also considered up for grabs, likewise offered encouraging signals to both sides. On the one hand, the chief justice said that nationwide marriage equality would have the negative effect of closing the debate on the issue, which in turn would “close minds.” But on the other, he seemed open to the idea that same-sex marriage bans constituted a form of sex discrimination, which would require an “exceedingly persuasive justification” in order to stand.

Bottom line: It can be very difficult to decipher what the justices are thinking based off oral argument, and the whole thing should be taken with a grain of salt.

“The general notion is that 90% of a case is won on briefs and 10% otherwise,” said University of Richmond law professor Carl Tobias to msnbc. “It’s really hard to predict the outcome based on arguments.”

“I’ve gotten out of that business,” he joked. “It’s too easy to get burned.”

Marriage Equality, SCOTUS and Supreme Court

What if gay marriage loses?