The biggest case the Supreme Court will decide this year went exactly as predicted: A packed house, colorful demonstrations outside the court, and virtually no access for anyone else. There was one unexpected glitch: At the end of the arguments by lawyer Mary Bonauto, who represented same-sex couples seeking a nationwide ruling on same-sex marriage, a protester interrupted the proceedings with a dire warning for the justices: “If you support gay marriage, you will all burn in hell.”

The demonstrator was quickly escorted out, but the moment illuminated the dynamics of Obergefell v. Hodges, a landmark case that should settle once and for all the legality of gay marriage—perhaps the biggest constitutional battle pitting civil and states’ rights since the Supreme Court decided Brown v. Board of Education more than 60 years ago. The court first took up the issue in 2013, when it voided the part of the federal Defense of Marriage Act defining marriage as between a man and a woman. But the arc toward equality for gays and lesbians began bending nearly 20 years ago, in Romer v. Evans, when a majority of the court ruled that the Constitution stood as a guard against the good intentions of a democratic majority willing to strip gays and lesbians of legal protections.

Against that backdrop, it was curious to hear the justices, including those on the court’s liberal wing, ask circumspect questions of Bonauto, a longtime advocate but a first-timer at the Supreme Court lectern. “What do you do with the Windsorcase, where the court stressed the federal government’s historic deference to states when it comes to matters of domestic relations?” fired Justice Ruth Bader Ginsburg, a staunch backer of gay rights and the first to raise tradition’s role in the proscription of marital relations. In that vein, other justices alluded to everything from same-sex relations in ancient Greece and Plato’s views to states’ prerogatives and the “millennia” of precedent where only opposite-sex marriage was enshrined at law.

Aside from a few moments where it seemed she was not addressing concerns by conservative justices, Bonauto held her poise—her argument was anchored on “the basic constitutional commitment to equal dignity” for gays and lesbians, the denial of which paints them with the “stain of unworthiness.” This tension between personal dignity and state autonomy to pass their own laws in family matters is the heart of what the justices will be deciding; it’s a conflict as old as the Constitution itself. Is it possible to grant a right to marriage to persons of the same sex, while not impinging on states’ prerogatives in the family sphere?

As if cognizant that court observers would be reading the tea leaves, it appeared the justices were unwilling to tip their hand in either direction. This explains why Justice Anthony Kennedy—author of every prior gay-rights victory and the expected swing vote in the case—made numerous appeals to the classic contours of marriage. “This definition has been with us for millennia,” Kennedy said. “It is very difficult for the court to say, ‘Oh well, we know better.’” Though one may interpret that as bad news for same-sex marriage, remember that Kennedy has had similar reservations in the past, and he’s come out on the side of equality every time.

The perpetual dissenter in gay-rights cases, Justice Antonin Scalia, seized on this moment, insisting that “not a single other society until the Netherlands in 2001” approved of marriage between people of the same sex. He suggested that it would be improper to vest judges with the power to decide for the entire country, or to assume that recent state bans are rooted in sudden LGBT animus. Can we trust nine unelected judges with such an important decision, or should final judgment be given to voters?

Playing devil’s advocate, Justice Stephen Breyer—a pragmatic respecter of institutions and the democratic process—pondered whether the ballot box would be the appropriate forum to settle the matter. In other words, to “wait and see” where the same-sex marriage debate heads on a state-by-state basis. (In a case last year, Breyer sided with conservatives to rule that voters could constitutionally ban affirmative action policies in higher education.) But Bonauto, clear that this is a case about the Constitution and principles of due process and equal protection, shot back: “‘Wait and see’ by itself has never been considered a legitimate justification, a freestanding justification under the Fourteenth Amendment.”

That didn’t seem to convince Chief Justice John Roberts, who is suspected to be in a power play with Kennedy over the authorship of Obergefell. Roberts worried that “closing the debate” on gay marriage “can close minds,” especially in light of slow but steady advancements in the states. “People feel very differently about something if they have a chance to vote on it than if it’s imposed on them by the courts,” Roberts said.

That has a federalist allure. But it is precisely this tentativeness—including Kennedy’s past double-edged rulings on gay rights—that has led to confusion in places where some constitutional normalcy would bring a measure of peace of mind to same-sex couples. Consider Alabama, where the state’s renegade chief justice has declared an all-out war against same-sex marriage, premised in part on voters’ reliance on the political process to amend the state constitution to shut out gays and lesbians from marriage.

In much the same way, should the Supreme Court agree that states have a right to “wait and see,” there’s no telling what chaos would follow. Not only would it leave same-sex couples on unequal footing—it would lead to years of protracted litigation, ill-advised legislative resistance, and more uncertainty for gays and lesbians wishing to make lifelong commitments. Under the Constitution, that result would be untenable. (The justices should know not to make the same mistake twice: It was its own standard of desegregation “with all deliberate speed” in Brown that led to long years of resistance from state holdouts, forcing the court a decade later to repudiate it and provide more clarity to school integration efforts.)

For all the discussions around equality and dignity, the court largely declined to delve much into whether laws targeting gays and lesbians are owed a higher level of constitutional scrutiny. This is a rather big omission: In all prior gay-rights rulings, the Supreme Court has refused to say whether laws directed at gays and lesbians deserve heightened scrutiny—as do laws premised on the basis of race or gender. This constitutional vacuum, in turn, explains why it’s perfectly legal in the majority of states to deny basic civil-rights protections to gays and lesbians in areas such as employment and housing. From oral arguments alone, it doesn’t seem like Obergefell will fill that void in the law.

But for everything that did occur inside the courtroom on Tuesday, there’s every indication that same-sex marriage will be the law of the land come late June. How the Supreme Court will reach that result is anyone’s guess. But for now it’s safe to say that it will follow the same pattern it has in the past: With liberals on one side, conservatives on the other, and the swing vote of Kennedy granting same-sex couples the right to marry in every state of the union. Will states also get a nod in the historic ruling? For better or for worse, you can bet on it.