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In the summer of 1988, abortion-rights attorneys debated whether to appeal a major abortion case involving minors, Hodgson v. Minnesota, to the Supreme Court. Anti-abortion lawyers working with Americans United for Life knew exactly why the opposition hesitated: Anthony Kennedy, a 52-year-old Catholic appointed by Ronald Reagan, had recently taken his place on the Supreme Court.

But instead of steadfastly opposing abortion, Kennedy quickly established his role as the Court’s swing vote on reproductive rights. With him gone, the future of legal abortion—and the activist movements surrounding it—is more uncertain than it has been in recent memory.

Kennedy searched for a middle ground in the abortion wars. He voted to uphold legal restrictions in cases involving partial-birth abortion, mandatory counseling, and parental involvement, as in Hodgson. Indeed, in more than 25 years on the Court, Kennedy voted to strike down abortion regulations only twice. In Planned Parenthood v. Casey, he helped create the undue-burden standard, which allowed states more leeway to regulate abortion. And he wrote more than once that women often regretted abortions (and that abortion providers did not always tell women what they needed to know).

But in some of the same cases, he voted to preserve the right to abortion. The Casey decision, which he helped write, retained much of Roe v. Wade. He repeatedly reinforced that abortion was a protected liberty, and at times, he highlighted women’s interests in equal treatment and autonomy. And in 2016, Kennedy joined an opinion that bolstered abortion rights by concluding that abortion is generally safe, and requiring states to show that any restrictions helped women in fact, not theory.

Kennedy worried about the dignity accorded to both fetuses and women, and he hoped that the Court could fairly weigh the two in each individual case. The result was a jurisprudence that satisfied neither pro-choice nor pro-life Americans. Indeed, after his retirement, liberals reminded one another that Kennedy was never really one of them. Abortion opponents celebrated the exit of a “pro-abortion” justice.

By pleasing no one, Kennedy left the country with a body of law that might reflect many Americans’ ambivalence about abortion. While the number of those who identify as pro-choice or pro-life has varied considerably over time, most Americans seem to want the same thing: for abortion to be legal, but (perhaps even quite heavily) regulated—a compromise Kennedy helped create.

The president’s allies want no such compromise. On the campaign trail, President Trump pledged to nominate “pro-life judges” who would overturn Roe. With Kennedy no longer on the bench and with a Republican majority in the Senate, there is little stopping the confirmation of a judge to cast that deciding vote. Liberals have bemoaned Kennedy’s departure with reason—the possibility that the Court will undo Roe has become a probability.

Yet in other ways, the future of abortion jurisprudence has become harder to predict with Kennedy gone. It is clear that anti-abortion advocates will ask the Court to overrule Roe—and soon. But so many of the strategies used by both sides reflected Kennedy’s beliefs and preferences. Abortion opponents had prioritized fetal-pain laws that built on Kennedy’s decision on partial-birth abortion. Relying on his opinions on post-abortion regret, other abortion foes promoted laws said to protect women from physical and psychological injury. We do not know if a sitting justice will become the new swing vote on abortion or if Trump will accidentally select the next Anthony Kennedy. And we have no idea which arguments will resonate with a reconfigured Court.

Among anti-abortion advocates, there is likely to be a heated debate about how to steer a post-Kennedy Court toward overturning Roe. Mainstream groups may wish to continue the incremental attack that is already under way. Proponents of personhood laws may champion another approach, as might those who have favored laws outlawing all abortions relatively early in pregnancy. Abortion opponents have introduced statutes that directly contradict Roe and Casey, such as an Iowa law banning abortion when doctors can detect a fetal heartbeat—as early as the sixth week of pregnancy. But quickly taking that legislation to the Court could be risky. Would five justices vote immediately to uphold such a law? Judges convinced that Roe is wrong might relish this opportunity. Or the new conservative majority might find such a change too abrupt—or think that jettisoning Roe so fast would appear political.

A Court without Kennedy might be receptive to an effort to slowly dismantle precedents supporting abortion rights. Some opponents have already argued that Casey and the cases following it are too vague to be workable. The justices could effectively reverse Roe without saying so, using the very undue-burden standard that Kennedy helped develop. The Court clarified somewhat the meaning of the standard in 2016, concluding that judges should weigh both the benefits and burdens of abortion regulations. But the standard is still quite vague, and much depends on the facts of individual cases. Without formally overturning Roe, the justices could uphold most or all abortion regulations that come before the Court.

It is even possible that abortion foes will ask the justices to go further, recognizing a constitutional right to life that would mean the criminalization of abortion nationwide. Certainly, abortion opponents have always wanted more than just the end of Roe.

But even without Kennedy, the odds of such a ruling seem remote. The kind of strict-constructionist judge Trump promises is usually skeptical about the recognition of rights not spelled out in the text of the Constitution. Antonin Scalia, the model for Trump’s new selection, famously criticized decisions identifying unenumerated rights, including ones that conservatives might support, like protections for parents. Even on a reconfigured Court, the right to life might be a hard sell.

And what of abortion-rights supporters—what will they do? The history of Kennedy’s early days on the Court might offer the best answer. The last time Roe was in jeopardy, in 1992, abortion-rights attorneys dared the Court to openly overturn Roe, hoping for a pro-choice backlash at the polls. It’s uncertain whether that bet would’ve paid off—the Court preserved Roe a few months before that year’s presidential election (though a pro-choice president, Bill Clinton, did win). Now, supporters of abortion rights are similarly focusing on the polls, with an eye toward November’s midterm elections.

Those supporters would know better than most that it can be devilishly hard to predict what a judge will do when the chips are down. After all, Anthony Kennedy was expected to cast the vote that put an end to Roe. His departure has been a game-changer, but it isn’t any easier to predict the future of the abortion debate than it was when he joined the Court.

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