People holding signs opposing abortion stand in front of the Supreme Court in Washington, D.C.Patrick Semansky / AP

Chief Justice John Roberts balked.

This morning, the Supreme Court announced its decision in June Medical Services v. Russo, the first big test of whether, and how, this Court—with two Donald Trump appointees—would revise abortion rights in the United States. When Trump was running for president, he explicitly promised to appoint judges who would “automatically” overturn Roe v. Wade, the case that established the constitutionality of abortion. Today, the Court has repudiated Trump’s promise with its decision in June Medical. While the ruling does not signal that abortion is safe at the Supreme Court, it’s a message that anti-abortion advocates cannot simply expect the Court to reverse abortion rights just because conservative justices now dominate the bench.

In 2018, when Justice Anthony Kennedy, who formerly acted as the Court’s main swing voter on social issues, announced his retirement, commentators were quick to pronounce abortion rights dead: “Abortion will be illegal in twenty states in 18 months,” tweeted the New Yorker writer Jeffrey Toobin. And yet, today, the liberal wing of the Court won.

June Medical concerns a Louisiana law that required doctors who perform abortions to obtain admitting privileges at nearby hospitals, which in theory meant they could immediately address emergency medical situations that arise during the procedure, but in practice served to limit the number of medical professionals who can legally terminate pregnancies. In the judgment of the Court, this case is nearly identical to one it decided just four years ago, Whole Woman’s Health v. Hellerstedt, about a strikingly similar law in Texas. When faced with the prospect of overturning such a fresh precedent—even though he disagreed with the outcome of that case—Roberts was unwilling to potentially undermine the legitimacy of the Court.

The Louisiana law that was at stake in June Medical embodies the anti-abortion movement’s strategy over the past decade. For at least the past 10 years, activists have pushed state-level regulations on abortion clinics. These restrictions are ostensibly designed to protect the health and safety of women. “The vast majority of Americans support patient-protection laws because they recognize that abortion practitioners should meet the same standard of care as any other physician,” Catherine Glenn Foster, the president and CEO of Americans United for Life, one of the national groups leading this effort, told me. When the Court considered a Texas law along these lines in Whole Woman’s Health v. Hellerstedt, however, it found that it placed an undue burden on women seeking abortions. June Medical Services effectively asked the new conservative majority on the Court to overturn precedent, effectively giving a green light to anti-abortion activists who have worked to restrict abortion at the state level.

[ Read: The Supreme Court will soon test its commitment to abortion rights ]

The composition of the Court appeared favorable to the challenge. Roberts voted with the minority in Whole Woman’s Health. And the new justices on the Court, Brett Kavanaugh and Neil Gorsuch, are both conservatives who have written passionately about the importance of religion in America and have expressed skepticism of the Court’s record on abortion rights. Despite these shared views on abortion jurisprudence, Roberts has recently been concerned about the Court’s partisan appearance. “I’ve always thought this [case] was a particularly difficult ask for Roberts, who has been very public about his concern for the Court’s reputation and institutional legitimacy,” Mary Ziegler, a law professor at Florida State University and the author of Abortion and the Law in America: Roe v. Wade to the Present, told me. In 2018, Roberts went so far as to rebuke the president’s claim that judges can be relied on to vote a certain way simply because of who appointed them: “We do not have Obama judges or Trump judges, Bush judges or Clinton judges,” he told the Associated Press. Cases concerning abortion are arguably the ultimate test of this principle. “It is a challenge for him, in this case, as many people would react to a Louisiana victory by accusing the Court of being an appendage of a political party,” Cary Franklin, a law professor at the University of Texas, told me.

In an opinion concurring with the majority decision, which was written by the liberal-leaning Justice Stephen Breyer, Roberts was explicit that he is not defending abortion rights. He is defending the Court. “I joined the dissent in Whole Woman’s Health and continue to believe that the case was wrongly decided,” he wrote. “The question today however is not whether Whole Woman’s Health was right or wrong, but whether to adhere to it in deciding the present case.” The legal doctrine of stare decisis, which means “to stand by things decided,” requires courts to treat similar cases alike, he wrote. Otherwise, it’s difficult for Americans to know what the law actually says. While Louisiana had argued that the facts of this case were substantively different from those in Texas, Roberts didn’t buy it. His unwillingness to go along with the argument that abortion regulations in each state should be treated differently is a clear signal to anti-abortion activists that they may have to shift their legal strategy. “It may be popping the balloon of the anti-abortion movement,” Ziegler said.

[ Read: The dishonesty of the abortion debate]

And yet, this decision does not mean that abortion rights will be automatically protected by the Supreme Court in future cases. Roberts was clear that he is still critical of the way Whole Woman’s Health was decided, and there are countless abortion-related challenges, focused on entirely different issues, currently winding their way through the federal court system. And the Court will likely continue to hear cases about incremental restrictions on abortion rights.

Although Trump’s appointments have shifted the Court in many significant ways, this case is a sign that the institution cannot be rapidly transformed to meet the political needs of the current administration. For groups that have worked closely with the president to change the makeup of the Supreme Court and limit abortion rights, the decision in June Medical is a major strategic loss. “Today’s ruling is a bitter disappointment,” said Marjorie Dannenfelser, the president of the Susan B. Anthony List, an influential anti-abortion-rights advocacy organization, in a statement. “It demonstrates once again the failure of the Supreme Court to allow the American people to protect the well-being of women from the tentacles of a brutal and profit-seeking abortion industry.” For activists and scholars who support abortion rights, however, this is a victory—not just because the Court decided in their favor, but because it shows that even controversial issues such as abortion will not be wholly decided by political imperatives. “We should celebrate because it’s also a sign that there’s something going on,” Aziza Ahmed, a law professor at Northeastern University, told me. “We can’t just assume that because we have a conservative majority, the right will always win.”

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