What You Need To Know About the Supreme Court Same-Sex Marriage Case, Which Starts Tuesday

Tuesday, the Supreme Court will hear arguments inObergefell vs. Hodges,the landmark civil rights case that will likely determine whether states should be forced to recognize gay marriage, or at least recognize same-sex marriages performed in other states.

This fall, it seemed like the same-sex marriage movement was actually pushed backward for the first time since the Supreme Court overturned the federal Defense of Marriage Act back in 2013. In November, a US Court of Appeals upheld state-level bans on same-sex marriage in Ohio, Tennessee, Kentucky, and Michigan.

That decision conflicted with other rulings in the lower courts, and so what seemed like a step back actually turned into a step forward for marriage equality. Because of the inconsistency in the lower court rulings, the Supreme Court agreed to step in, rolling all of the suits from those four states together into a case that is expected to decide the issue once and for all.

The lead plaintiff, 40-year-old Jim Obergefell, was merely the first to file an appeal—a decision he made as his partner of more than 20 years was dying of ALS. Although his partner, John Arthur was bedridden, the couple managed to fly out of Ohio—which does not recognize same-sex marriage—to Maryland, where the two married on the tarmac at Baltimore International Airport.

Although Arthur has since passed away, Obergefell will now have the privilege of listening to the Supreme Court's oral arguments Tuesday over whether or not Ohio should recognize their marriage. Right now, Obergefell is not listed on his spouse's death certificate.

There are three possible outcomes to Obergefell vs. Hodges.The judges could decide that all states must issue licenses to gay couples—a result that would mean the question of same-sex marriage in America would be put to rest, forever. The second possibility is that the judges could decide solely that other states must recognize marriages performed in other states where it's legal. Or, the justices could decide to let the states continue to do their own thing.

Of course, people have tons of opinions about this. As such, a huge list of parties submitted amicus briefs to the court in an attempt to influence the justices. Groups like PFLAG and the Family Research Council obviously had their say, although some interested parties were much less predictable, such as the group of gay Mormon men married to women who said gay marriage would make their lives "meaningless."

The court's decision will depend in part on whether the judges view gay people as a certain kind of people or people who engage in a certain act. Classes of people are constitutionally protected, and acts aren't necessarily. Groups like the American Psychological Association have pointed out in briefs that homosexuality is an immutable characteristic, and that thereforedenying gay couples the right to marry "stigmatizes them" as a group.Opponents, needless to say, have argued the opposite.

But more than science, the case is about states rights and the Fourteenth Amendment—specifically, whether the definition of "marriage" should be decided by each state, or whether the federal government has the right to step in and end a debate that's been raging for years. Gay couples and their supporters argue that they simply want equal access to a right that's been established in every state. Opponents claim this amounts to asking the Supreme Court to establish a new constitutional right—essentially contending that "gay marriage" is a completely separate entity than "traditional marriage."

So yes, it's really kind of complicated. Or at least, a lot more complicated than sticking a Human Rights Campaign sticker on your car and declaring tautologies like "love is love."

To Obergefell, though, it really is that simple. Before he headed to Washington D.C., he told NBC News that he and his husband didn't really focus on the upcoming court cases in the final months of his life, but that Arthur would have wanted him to be recognized on his death certificate.

"I would like everyone to think about the end of their life and their death certificate, their last official record as a person," he said. "Do they want that record to be accurate or not? Do they want that record to reflect their life, their love and their commitment?"

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