Melissa Murray is the Frederick I. and Grace Stokes Professor of Law at New York University School of Law.

Depicted as a serpent or a dragon eating its own tail, the ouroboros in Greek mythology was interpreted as a symbol of eternal renewal — the infinite cycle of life, death and rebirth. Now, the ouroboros lives on in the Supreme Court’s abortion jurisprudence and in the court’s invocation of the doctrine of stare decisis.

Latin for “let the decision stand,” stare decisis has shaped the court’s abortion jurisprudence — and the public debate over abortion rights. Consider the calls to overrule Roe v. Wade, the 1973 Supreme Court decision that recognized a woman’s right to choose an abortion. Although abortion opponents insist that Roe is both morally abhorrent and constitutionally unprincipled, the court, citing deference to precedent, has declined multiple invitations to overrule the decision.

The court again relied on stare decisis Monday to beat back another assault on abortion rights in June Medical Services v. Russo. This time, the court’s liberal wing teamed up with Chief Justice John G. Roberts Jr. to strike down a Louisiana law that required abortion providers to have admitting privileges at local hospitals. To be sure, Roberts is no supporter of abortion rights — he dissented in Whole Woman’s Health v. Hellerstedt, the court’s 2016 decision invalidating a Texas admitting privileges law. But in the role of chief justice, he is perhaps the most stalwart defender of the court’s legitimacy, and in Monday’s decision, he emphasized the importance of “adherence to precedent” for maintaining the “actual and perceived integrity of the judicial process.” With these words, abortion rights live to fight another day.

If all of this feels familiar, it should. Similar dynamics were at play 28 years ago when the court decided Planned Parenthood v. Casey. Then, as now, the question of precedent loomed large as abortion rights groups braced for the court, with its new complement of Reagan and George H.W. Bush appointees, to scuttle Roe. Instead, the court, in an apparent nod to precedent, affirmed Roe’s “essential holding” that there was a constitutional right to choose an abortion.

But Casey was far from an unadulterated endorsement of Roe. Indeed, in contrast to Roe, which required state legislation restricting abortion to meet a punishing constitutional standard, Casey lowered the standard by which abortion laws would be judged, giving states more latitude to impose conditions on the abortion right, so long as the restrictions did not pose an “undue burden.” Emboldened by Casey and its less rigorous standard, states enacted a spate of laws that imposed a litany of conditions on abortion providers and patients, strangling abortion access and burdening those seeking to exercise the abortion right. Despite its professed allegiance to precedent, many argue that Casey, in rendering the abortion right a nullity for many women, effectively overruled Roe.

June Medical seems ripped from the Casey playbook — a victory scaffolded by lofty talk of precedent and stare decisis. Roberts makes clear that his decision to join the court’s liberals is guided solely by respect for precedent. The law challenged in June Medical is the twin of the Texas admitting privileges law invalidated in Whole Woman’s Health. And if like cases are to be treated alike, Roberts wrote, Whole Woman’s Health requires invalidating the Louisiana law challenged in June Medical.

But Roberts’s respect for precedent goes only so far. Meaningfully, he does not endorse Whole Woman’s Health’s reasoning, which required courts to weigh whether an abortion law’s purported benefits exceeded the burdens imposed. Instead, Roberts rejected this logic, concluding that in determining the constitutionality of an abortion restriction, courts need consider only whether the law places a “substantial obstacle” in the path of a woman seeking an abortion. In the name of stare decisis, Roberts reiterates Whole Woman’s Health’s outcome, while completely disavowing its reasoning and its protections for abortion rights.

In this way, Roberts’s decision in June Medical Services does to Whole Woman’s Health what Casey did to Roe. It preserves the outer shell of the earlier decision while gutting its substance. And in so doing, it invites states to push the envelope on abortion legislation, secure that, regardless of the benefits to patients, courts will bless the laws so long as they do not pose a substantial obstacle.

For years, in their defense of Roe and abortion rights, reproductive rights advocates have underscored the importance of stare decisis and precedent. But what these appeals to the past overlook is that precedent, like anything else, can be deployed for good or for ill, and in some cases may do both simultaneously. Like the mythical ouroboros that consumes itself in an endless cycle of death and life, stare decisis once again is the vehicle for preserving the court’s abortion jurisprudence while also destroying it.

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