For full coverage of June Medical Services v. Russo, check out our Special Report.

For the last several months, abortion rights enthusiasts have eyed Chief Justice Roberts nervously, waiting to see if he would blow up the U.S. Supreme Court’s abortion rights jurisprudence in June Medical Services v. Russo, a case about whether a hospital admitting privileges law that the Court already said was unconstitutional four years ago was still unconstitutional.

On Monday, advocates were pleasantly surprised when Roberts sided with Justices Breyer, Ginsburg, Kagan, and Sotomayor to answer that question in the affirmative. But, because we’re talking about abortion rights and the Supreme Court, even a win like Monday’s can’t be easy or straightforward.

Lawmakers in Louisiana passed Act 620 specifically because an identical law in Texas led to mass clinic closures, and Louisiana craved those same results. Indeed, just like lawmakers in Texas, lawmakers in Louisiana made it clear that the point of the clinic shutdown law was exactly that: to shut down clinics. And like Texas did in Whole Woman’s Health v. Hellerstedt four years ago, Louisiana argued in June Medical Services that it enacted the law to promote the health and safety of pregnant people.

But Justice Stephen Breyer, who penned the opinion in Whole Woman’s Health four years ago, wasn’t buying what Louisiana was selling. He pointed out that the Louisiana law was “almost word-for-word identical” to the Texas law, before expertly dismantling Louisiana’s efforts to defend it.

Like the Texas clinic shutdown law, Louisiana’s law requires abortion providers to maintain admitting privileges at a local hospital. And, as in Texas, the law in Louisiana provided no medical benefit for pregnant people and no credentialing function for providers.

So how did the Louisiana case even end up before the Supreme Court?

Some of it is timing: Louisiana enacted its clinic shutdown law before the Supreme Court dropped Justice Stephen Breyer’s downright nerdy opinion striking down Texas’ identical law in Whole Woman’s Health.

But some of it was a calculation based on the current makeup of the Court: In 2016, Kennedy provided the deciding vote to strike down Texas’ clinic shutdown law. But by the time the Court heard June Medical Services, Kennedy had retired and been replaced by Kavanaugh, meaning that the deciding vote would be Roberts’.

And considering that Roberts sided with the conservatives to uphold Texas’ clinic shutdown law in 2016, it was a fair calculation that Roberts might choose to ignore Whole Woman’s Health as precedent and uphold Louisiana’s identical law.

So Louisiana went for it, trying to differentiate its clinic shutdown law from Texas’ in the hopes that Roberts might bite. He didn’t—and that’s because Louisiana had no leg to stand on.

The district court conducted a six-day trial during which it considered and accepted testimony from abortion providers who described at length the ways that obtaining admitting privileges is a profound pain in the ass. Some hospitals flat out refuse to give abortion providers admitting privileges for religious reasons. Other hospitals require doctors to have a certain number of admissions in order to qualify for admitting privileges. Ironically, because abortion is so safe, abortion providers cannot guarantee a minimum number of admissions. If they could, it would mean that they are bad at their job, and the state would likely launch investigations demanding to know why their abortion complication rate is so high and therefore outside the norm. It’s a “damned if you, damned if you don’t” situation.

Louisiana also launched an attack against a principle called third-party standing, which, for nearly 45 years, has permitted abortion providers to challenge nonsense abortion regulations like Louisiana Act 620 on behalf of not only themselves, but their patients as well. Again, Roberts didn’t bite.

But had Louisiana launched an even more direct attack on precedent out of the gates, it likely would have found a friendly ear in Roberts, even though he penned an entire concurring opinion about how precedent is the only reason he joined his liberal colleagues on Monday to strike the Louisiana law. And that is something that abortion rights advocates should be concerned about.

For all his preening about the importance of stare decisis, Roberts fired a warning shot at the future of abortion rights law. In his concurring opinion, Roberts noted that “neither party has asked us to reassess the constitutional validity” of the Court’s “undue burden” standard, before going on to do just that. “Undue burden” has been the framework used for judging abortion rights restrictions since the standard was laid out in the historic Planned Parenthood v. Casey decision that upheld Roe v. Wade in 1992. Launching into a multipage diatribe against Casey and against Breyer’s interpretation of that case, Roberts makes it clear that while he voted to uphold abortion rights on Monday, he can’t be counted on to do so again in the future.

In Roberts’ estimation, Breyer has got it all wrong when it comes to Casey, first when Breyer cited it in Whole Woman’s Health and then again on Monday when he cited it in June Medical Services. In Breyer’s world, the undue burden analysis mandated by Casey requires a balancing test between the burdens the law may impose on the right to abortion against the benefits the law purports to have. If the burdens outweigh the benefits, then the law imposes a substantial burden on abortion rights and violates the Casey undue burden standard. When it comes to admitting privileges laws like Louisiana’s, there’s no medical benefit. End of story.

But Roberts doesn’t believe that Casey requires a balancing test that weighs the costs and purported benefits of an abortion regulation. There’s no meaningful way that the Court could weigh a state’s interest in protecting the potentiality of human life against a pregnant person’s liberty interest, in Roberts’ view. (A view which is, frankly, somewhat bizarre since courts frequently balance the rights of a state against the rights of an individual. In cases involving religious rights, for example, the outcome frequently boils down to a balancing of state rights against individual rights. Courts love balancing tests almost as much they love three-pronged tests.)

For Roberts, however, the Casey analysis begins and ends with one question: Is this law a substantial obstacle to abortion? It’s a yes-or-no question, one Roberts proposes be answered in a vacuum without reference to the benefits and burdens that will determine whether or not an obstacle is substantial. That’s because, according to Roberts, when courts weigh burdens and benefits they come dangerously close to legislating from the bench.

But that doesn’t make any sense. If a law doesn’t provide the benefit that the proponent of a law says it does, then what is the point of the law? States can’t just restrict constitutional rights for funsies, and Roberts knows this. If a state law forces providers to jump through hoops for reasons that are not based in reality but rather reflect the state’s anti-choice bias, then the point of that law isn’t a reasonable restriction of a constitutional right. It’s just harassment.

And if the law provides some small benefit, why shouldn’t that benefit be weighed against the burdens that the law imposes? What else are courts to do when reviewing the constitutionality of laws that affect fundamental rights? Just rubber-stamp them, as the Fifth Circuit and Roberts’ fellow conservatives on the bench would do?

These are questions that Roberts is happy to save for another day. And, critically, these are questions that Justice Samuel Alito is champing at the bit to answer. In his angry and lengthy dissent, Alito agrees with Roberts that Casey does not require a balancing test, and he would be more than happy to help Roberts blow a hole through Casey.

I can envision a world where Alito writes the majority opinion taking down Casey. That would be especially sweet for him, since he was a judge on the Third Circuit panel that heard the Casey appeal in 1991, and would have upheld the entire Pennsylvania abortion law, including the parts that the Supreme Court would ultimately strike down in 1992. Alito even upheld the yikes-inducing spousal notification provision that would have forced pregnant women to tell their potentially abusive husbands that they intend to get an abortion. Alito and Roberts could easily team up to take down Casey; on Monday, Roberts all but invited anti-choice advocates to tee up a case for the conservatives to do just that.

For now, though, Roberts agrees with the liberals that Louisiana’s law is horseshit, and that will just have to be enough. Because, damnit, abortion rights supporters needed a win in June Medical Services. There will be another fight another day. Roberts’ vote and opinion Monday guarantees it.