In 1992, the Supreme Court looked poised to overturn Roe v. Wade, the landmark case protecting abortion rights. They didn’t, however, and the main reason was respect for precedent—specifically, the legal doctrine known as stare decisis, or “let the decision stand.”

Would it do the same today, with over 250 laws meant to test the case pending in states across the country?

An otherwise obscure case decided this week, Franchise Tax Board of California v. Hyatt, suggests that a majority of the court would not.

Hyatt was, in large part, about stare decisis. A 1979 Supreme Court case, Nevada v. Hall, held that citizens can sue a state in another state’s court. In 1998, Gilbert Hyatt did just that as part of a tax dispute, with tens of millions of dollars at stake. This week, the court overruled its 1979 decision by a vote of 5-4 and tossed out Hyatt’s claim. The split was on ideological lines, with the court’s five conservatives in the majority and four liberals in the minority.

Of the 18 pages in the majority opinion written by Justice Clarence Thomas, 17 are about the legal question in the case, which revolves around states’ rights, sovereign immunity, and the Constitution. It’s no surprise that Justice Thomas, in particular, wrote this opinion, as states’ rights have been a focus of his for three decades.

“ If this same standard is applied to Roe and Obergefell, they would go down in flames. ”

What was surprising is that stare decisis warranted only 318 words in Justice Thomas’ opinion, almost like an afterthought, and that Justice Thomas summarily waved away this important judicial doctrine.

If this is how the court’s conservatives treat sovereign immunity, how will they treat abortion rights?

That’s what Justice Stephen Breyer asked in his dissent. Unlike the majority opinion, Justice Breyer’s dissent devoted over a quarter of its space to stare decisis. And he concluded, “today’s decision can only cause one to wonder which cases the Court will overrule next.”

It’s not hard to guess which cases Justice Breyer was wondering about. Because the same logic applied in Hyatt would overturn not only Roe v. Wade but also the court’s precedent on same-sex marriage, Obergefell v. Hodges.

How? Let’s look at Justice Thomas’ reasoning.

First, Justice Thomas notes that stare decisis is “‘not an inexorable command” and is “at its weakest when we interpret the Constitution because our interpretation can be altered only by constitutional amendment.”

Now, some would say that stare decisis is at its strongest when fundamental constitutional rights are at issue. But for Justice Thomas, in cases like Roe and Obergefell, stare decisis is at its “weakest.”

Thomas then goes on to apply a version of the usual stare decisis test, taking into account “the quality of the decision’s reasoning; its consistency with related decisions; legal developments since the decision; and reliance on the decision.”

The first prong is the most important. Here, Thomas finds that the 1979 precedent “failed to account for the historical understanding of state sovereign immunity.” But that’s not the same as the decision’s being of poor quality—it’s an imposition of Justice Thomas’ specific, historically oriented “originalism” philosophy.

There are, after all, many ways to evaluate the quality of a decision’s reading: its principled analysis of the rights in question, its integration of constitutional norms with contemporary reality, and so on.

Here, however Justice Thomas glosses over that jurisprudential debate and simply concludes that a Supreme Court precedent was badly argued—according to his standards.

This is the central question in cases like Roe and Obergefell. No one denies that abortion was banned for much of our country’s history, and that same-sex marriage would have been anathema to the Founders of the republic. The debate is over whether history gets a vote or a veto.

If this same standard is applied to Roe and Obergefell, they would go down in flames.

The fourth prong is also critical. People depend on the law being stable. Hyatt, for example, filed his suit exactly as the law provided. Now, the rug is pulled out from under him, and all Justice Thomas says is that “we acknowledge that some plaintiffs, such as Hyatt, have relied on Hall by suing sovereign States. Because of our decision to overrule Hall, Hyatt unfortunately will suffer the loss of two decades of litigation expenses and a final judgment against the Board for its egregious conduct.”

Unfortunately!

Now multiply Hyatt’s misfortune a millionfold. As Justice Breyer wrote, overturning Supreme Court precedents except in the rarest of cases “is to cause the public to become increasingly uncertain about which cases the Court will overrule and which cases are here to stay.”

Arguably, many more people rely on Roe and Obergefell than on Hall, and so the reliance prong would be more important in challenges to those cases.

But that cuts both ways. For every woman seeking an abortion, there is someone who believes that abortion is murder. In at least a dozen states, a majority of democratically elected legislators are trying to ban or severely limit the practice. Just last week, Georgia became the fourth state this year (joining Kentucky, Mississippi, and Ohio) to ban abortions after only six weeks of pregnancy, in a direct frontal challenge to Roe. And, a future conservative justice might point out, women seeking abortions could simply travel to other states if need be (if, of course, they can afford it).

Because Justice Thomas so readily dismisses the reliance claim in Hyatt, it’s easy to see him doing the same in Roe.

Likewise in Obergefell. For 12 years, we lived in a country in which same-sex marriage was legal in some states and illegal in others; is a return to such a world truly untenable? Anyway, unless marriages like mine were retroactively invalidated, who is really relying on same-sex marriage being legal? Prospective couples could, like victims of rape or incest, simply relocate to a state more favorable to their interests.

In short, Justice Thomas’ theory of stare decisis is like a roadmap for how to overrule decisions one disagrees with. First, frame the disagreement as one over “quality” rather than principle. Second, trivialize the ways in which people rely on the law as it stands.

And third, with the stroke of a pen, wipe out constitutional rights that people like me mistakenly think we possess.