Since last summer’s decisions in United States v. Windsor and Hollingsworth v. Perry striking down the federal definition of marriage as a union between one man and one woman and upending California’s Proposition 8, there has been a flood of litigation seeking to overturn similar state-level same-sex marriage bans. All told, there have been 65 federal court decisions in favor of marriage equality and three against, with cases still pending in the Eighth, Tenth, and 11th Circuit Courts of Appeals.

On Tuesday, April 28, the Roberts Court will tackle the questions left open from those cases, primarily whether or not states can ever ban, or fail to legally recognize, same-sex marriages. Tuesday’s arguments before the Court involve challenges to same-sex marriage bans in Ohio, Tennessee, Michigan, and Kentucky via a decision from the U.S. Court of Appeals from the Sixth Circuit to allow those four bans to stand.

What Are the Arguments?

When the Court granted review of those four cases in January, it limited the questions to two: (1) whether the U.S. Constitution requires states to allow same-sex couples to marry; and (2) whether the Constitution requires states where same-sex marriage is not legal to recognize the marriages of same-sex couples who were legally married in another state.

The states defending their marriage bans argue, basically, that it is a states’ right to define marriage how it wants, including restricting it to a union between one man and one woman. This argument is the strongest in Michigan’s brief, which relies heavily on the Roberts Court decision last summer in Schuette v. Coalition to Defend Affirmative Action to allow state voters the right to ban the use of race in public university admissions. Because advocates and pundits widely believe that Justice Kennedy will be the “swing vote” on marriage equality, and because he authored the opinion in Schuette, Michigan’s brief seems clearly designed to force him to choose between supporting marriage equality and his own precedent.

The state’s attorneys argue in the brief that the law is not mean-spirited bigotry. Instead, they claim, leaving the marriage question to the states allows citizens to shape “the course of their own times,” which also properly respects the division of governmental powers between the federal government and the sovereign states. Other briefs in support of statewide marriage bans echo the themes of letting states and their voters decide which citizens deserve equal rights and which ones do not.

Attorneys representing the same-sex couples, meanwhile, argue these cases are all about an access to a fundamental constitutional right—in this case, marriage. They say that the Constitution, specifically both the equal protection clause and the due process clause of the 14th Amendment, prevents states from erecting barriers to those fundamental rights without good reason. The equal protection clause, they argue, prevents states from specifically excluding LGBT individuals from marriage benefits and also denying them the same legal process as opposite-sex couples. Marriage equality advocates argue there is no good reason, besides anti-LGBT hostility, for states to ban same-sex marriage or to not recognize same-sex marriages performed in another state.

Furthermore, the couples point out, they are not trying to create a new right. In other words, they are not arguing for a constitutional right to same-sex marriage. They are arguing for an equal right to enter into the historical institution of marriage.

What Are the Possible Outcomes?

The Supreme Court could rule that states are both required to allow same-sex couples to marry as well as recognize the marriages of same-sex couples who were legally married in another state. It could rule that states are not required to either allow same-sex couples to marry or recognize same-sex marriages from other states. Or the Court could split the difference and somehow rule that states don’t have to allow for same-sex marriages in their borders but must recognize those legal same-sex marriages from other states. That last seems unlikely, given the legal gymnastics it would take the Court to get there as well as the logistical nightmares the ruling would spawn, but this is the Roberts Court, so anything is possible.

More likely than not, though, a majority of justices will take the first option and rule in favor of marriage equality. That doesn’t mean, however, that the issue of marriage equality is solved. Presuming the Court takes the first path, the fight will then shift full-tilt to so-called “religious freedom” statutes sweeping conservative states as those ideologically opposed to same-sex marriage look to shield themselves from having to engage, even remotely, with same-sex couples. More bakers, florists, and pizza makers will insist on an affirmative right to discriminate in the name of religion. Furthermore, conservatives will likely look to build off last summer’s “religious freedom” win in Hobby Lobby by arguing that a sincerely held religious belief against same-sex marriage protects them from having to recognize the civil rights that flow from the Court recognizing marriage equality.

That’s not to say progressives shouldn’t still push for employment protections and related civil rights recognition for LGBT individuals and couples. We should and we must. It’s to say that conservatives know marriage equality is a culture wars battle they’ve lost, so instead they’ve turned their sights to where they think they can win.

When Will We Know the Outcome?

As soon as the justices are ready! In the meantime, for those of you who just can’t get enough of the Supreme Court and the fight for marriage equality, the Roberts Court announced it was taking the unprecedented step of making both the audio and written argument transcripts available the same day of oral arguments instead of later. The next thing you know, the Court will go totally bananas and let cameras in the courtroom! Just kidding, we know that’s never going to happen.

In terms of when the Roberts Court will release its opinion, though, I’d say that given the magnitude of the issues and the fact that the Court is hearing arguments relatively late in its calendar, mark your calendars for the end of June, right before the close of the Court’s term.