In a blockbuster announcement Monday, the U.S. Supreme Court agreed to take a case that could end Roe v. Wade’s guarantee of abortion rights throughout the United States. Since September, the court has been considering whether to take Dobbs v. Jackson Women’s Health Organization, a challenge to Mississippi’s law banning most abortions after 15 weeks. Some observers thought that because the Supreme Court did not take action on the petition for eight months, the new six-justice conservative majority had no interest in wading into the abortion wars. Apparently, they were wrong.

In Dobbs, the Supreme Court will consider whether states can ban abortion before viability, the point at which survival is possible outside the womb. The court may directly overrule Roe, its landmark abortion ruling. But even if Dobbs stops short of that, the court’s decision to take the case is the biggest news in abortion politics for decades. That’s for one reason: the constitutional importance of fetal viability.

What Dobbs is about

In 2018, Mississippi lawmakers passed a law banning abortion after 15 weeks, with exceptions for certain medical emergencies and severe fetal abnormalities. Groups such as the National Right to Life Committee and the Susan B. Anthony List were pursuing a strategy of banning abortion after, they claimed, fetuses could experience pain, and the law followed that strategy. Most research finds that fetuses cannot experience pain until later in pregnancy — around the 29th or 30th week. Nevertheless, laws such as this — most banning abortion at 20 weeks — ended up on the books in 18 states.

Abortion providers challenged the law. In 2018, a district court held that Mississippi’s law was unconstitutional. The generally conservative Fifth Circuit Court of Appeals upheld that decision. Since 1973’s Roe v. Wade, the Supreme Court has ruled that women have the right to choose abortion until the fetus is viable, generally between 22 and 24 weeks. The Fifth Circuit held that because Mississippi’s law violated Roe, it had to go.

The state of Mississippi appealed. This week, the court announced it would hear arguments on the case’s most explosive question: Could states ban abortion before viability?

The viability standard and its critics

In Roe v. Wade, the Supreme Court declared that the right to privacy encompassed a woman’s decision to end a pregnancy. But the court went to great lengths to stress that that right was not absolute: After viability, states could ban abortion outright.

Viability made some sense. Once a newborn could survive outside the womb, the pregnant woman’s autonomy and bodily integrity was no longer irreconcilably in conflict with fetal rights. But quite early on, many saw viability as one of Roe’s weaker points. Bioethicists and philosophers argued over whether fetal life gained moral value before viability.

Even Justice Sandra Day O’Connor, the swing vote in upholding the core right in Roe decades later, wrote in the 1983 case City of Akron v. Akron Center for Reproductive Health that viability was an unworkable standard for abortion regulation. She argued that lawmakers lacked the scientific chops to know whether technology made viability possible earlier in pregnancy, and when or whether to update their rules. Nor did courts have the scientific know-how to second-guess lawmakers. To paraphrase, O’Connor argued that using viability as the standard was a mess.

Antiabortion activists have focused on viability since the 1980s

For decades, antiabortion activists have tried to capitalize on uncertainty about when viability begins. In the 1980s, states passed laws redefining viability or requiring several doctors to be present at abortion procedures after the state believed that viability was possible.

Abortion foes have attacked the viability standard from several angles. Some laws, such as the what are known as “reasons bans,” introduced in states such as Ohio and Arkansas stop people from having pre-viability abortions in cases of Down syndrome or sex selection, on the grounds that those are not valid reasons to terminate a pregnancy. States such as Texas are banning medication abortion or dilation and evacuation, the most common method after the first trimester, before viability. And “heartbeat bills” would ban abortion after doctors can detect fetal cardiac activity, an alternative to viability.

If the Supreme Court abandons the viability standard, states may ban abortion altogether

Viability has long been a cornerstone of abortion jurisprudence for a reason. Especially since 1992, when the court decided Planned Parenthood v. Casey, the justices have balanced pregnant people’s interest in autonomy, equality and bodily integrity and the state’s interest in protecting fetal life.

Viability has always been the dividing line. Before that moment, the pregnant woman can decide; after that moment, the state can protect the fetus. But if viability goes, the court may allow abortion bans much earlier in pregnancy — or even entirely.

In the summer, in the Supreme Court’s June Medical Services v. Russo decision, Chief Justice John G. Roberts Jr. discussed what will probably be the abortion rights movement’s main argument. June Medical struck down a Louisiana law requiring abortion providers to have admitting privileges at a nearby hospital. Roberts agreed to strike down the law to protect the court’s past decisions. Even if the court’s conservatives don’t believe there is a right to choose, they may hesitate to undo 50 years of jurisprudence, unleashing a possible political backlash.

But if the court eliminates viability, a centerpiece of abortion jurisprudence since the beginning, respect for precedent would be a much tougher argument to make. The court has already rejiggered abortion case law more than once. What would be left?

This may set off the slow death of Roe v. Wade

The Supreme Court will hear Dobbs in the 2021-2022 term, probably deciding it by June. That ruling will affect politics in the 2022 midterm elections and beyond. Upending decades of abortion jurisprudence will be questionable — with voters, who will have a chance to change the Senate, and with the Biden administration, which has convened a commission to consider changing the Supreme Court’s composition. Dobbs may be the beginning of the end for Roe, but the abortion wars are far from over.

Mary Ziegler (@maryrziegler) is the Stearns Weaver Miller Professor of lawat Florida State University College of Law, and author of “Abortion and the Law in America: Roe v. Wade to the Present” (Cambridge University Press, 2020).

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