(WASHINGTON) — The U.S. Supreme Court on Wednesday heard historic arguments over a Mississippi law that would ban most abortions after 15 weeks of pregnancy, with conservative justices openly raising the prospect of overturning decades of legal precedent since the Roe v. Wade decision legalizing abortion nationwide.

After almost two hours, the conservative majority appeared headed toward changing 30 years of settled law protecting a woman’s right to end a pregnancy before fetal viability and upholding the Mississippi ban, which legal scholars say could clear the way for stringent new restrictions on abortion in roughly half the country.

“Viability it seems to me has nothing to do with choice,” said Chief Justice John Roberts. “Why is 15 weeks not enough time?”

“That’s not a dramatic departure from viability,” Roberts added of the state law and the line it would draw.

Since the 1973 landmark Roe ruling and the 1992 Planned Parenthood v. Casey case that affirmed the decision, the court has never allowed states to prohibit the termination of pregnancies prior to fetal viability outside the womb, roughly 24 weeks, according to medical experts.

Mississippi argues Roe was wrongly decided and that each state should be allowed to set its own policy.

Scott Stewart, the solicitor general of Mississippi and a former clerk to Justice Clarence Thomas, spoke first, saying that the precedents the Supreme Court set with Roe and Casey in 1992 “damaged the democratic process” and “poisoned the law,” adding, “they’ve choked off compromise.”

“For 50 years they’ve kept this court at the center of a political battle that it can never resolve,” he said.

Justice Sonia Sotomayor questioned whether the court should have taken up the case since the legal right to an abortion based on viability has been a long-standing precedent.

“There has been some difference of opinion with respect to undue burden, but the right of the woman to choose, the right to control her own body has been fairly set since Casey and never challenged. You want us to reject that viability line and adopt something different,” she said. “Thirty (justices) since Casey have reaffirmed the basic viability line. Four have said no to the members of this court, but 15 justices have said yes or varying political backgrounds.”

Referring to comments from a Mississippi lawmaker, she said, “The Senate sponsor said we’re doing it because we have new justices on the Supreme Court,” noting the new makeup of the court with three conservative justice appointed by former President Donald Trump.

“Will this institution survive the stench that this creates in the public perception that the Constitution and its reading are just political acts?” she asked.

Justice Stephen Breyer stressed the importance of stare decisis — the legal principle that courts generally adhere to precedent.

“To overrule under fire in the absence of the most compelling reason to reexamine a watershed decision would subvert the court’s legitimacy beyond any serious question,” Breyer said.

Jackson Women’s Health and its allies say the high court’s protection of a woman’s right to choose the procedure is clear, well-established and should be respected.

But the current court, with a 6-3 conservative majority, is widely considered more sympathetic to abortion rights opponents than any in a generation.

Conservative justices homed in on the current viability standard of roughly 24 weeks, with Justice Samuel Alito describing the line set as “arbitrary.”

As Julie Rikelman of the Center for Reproductive Rights, representing Jackson Women’s Health Organization, the only abortion clinic in Mississippi, argued the impact of pregnancy, Alito responded, “If a woman wants to be free of the burdens of pregnancy, that interest does not disappear the moment the viability line is crossed,” adding, “The fetus has an interest in having a life, and that doesn’t change from the point before viability and after viability.”

When Justice Thomas asked her to identify the constitutional right at issue — whether to abortion, privacy or autonomy, Rikelman replied, “It’s liberty.”

“It’s the textual protection in the 14th Amendment that the state can’t deny someone liberty without the due process of law,” she said.

“Allowing a state to take control of a woman’s body and force her to undergo the physical demands for risks and life-altering consequences pregnancy is a fundamental deprivation for liberty, and once the court recognizes that liberty interest deserves heightened protection, it does need to draw a workable line of viability that logically balances the interests at stake,” Rikelman added.

Justice Brett Kavanaugh asked if the court’s decisions in Roe and Casey were wrong to begin with, how that would counter the stare decisis principle.

“The Constitution is neither pro-life nor pro-choice on abortion. If we think that the prior precedents are seriously wrong, why don’t we return to neutrality? Doesn’t the history of this court’s practice with respect to those cases tells us that the right answer is actually a return to the position of neutrality, and not stick with those precedents in the same way that all those other cases did?”

Later, Kavanaugh asked Solicitor General Elizabeth Prelogar, arguing the Biden administration’s support for abortion providers, “Why should this court be the arbiter rather than Congress?”

“There’ll be different answers in Mississippi in New York, different answers and Alabama than California because they’re two different interests at stake and the people in those states might value those interests somewhat different way,” Kavanaugh said, signaling he might support handing the issue back to the states, despite saying at his confirmation hearings that Roe was “settled law.”

Prelogar replied that it’s not up to states to decide whether to honor fundamental rights.

A former clerk to the late Justice Ruth Bader Ginsburg and Justice Elena Kagan, Prelogar earlier said, “The court has never revoked a right that is so fundamental to so many Americans and so central to their ability to participate fully and equally in society. The court should not overrule the central component of women’s liberty.”

Justice Amy Coney Barrett, who’s personal views on abortion factored large during her confirmation hearing last year, raised doubts about how sweeping the impact would be if the court sides with Mississippi. “Don’t Safe Haven Laws take care of that?” she said, referring to legislation in nearly every state allowing a parent to abandon a newborn baby without fear of prosecution in the event life circumstances make them unable to parent.

Majorities of Americans support the Supreme Court upholding Roe v. Wade and oppose states making it harder for abortion clinics to operate, according to an ABC News/Washington Post poll this month. Three in four Americans, including majorities of Republicans, independents and Democrats, say the decision of whether or not to have an abortion should be left to a woman and her doctor.

But Americans appear more sharply divided on the type of ban at issue in Mississippi. A Marquette University Law School poll this month found 37% favored upholding a 15-week ban, with 32% opposed.

Overshadowing the case is the Supreme Court’s still-pending decision in a separate dispute over Texas’ unprecedented six-week abortion ban, SB8, which has been in effect for nearly three months and dominated national headlines.

The justices gave the Texas law a highly expedited hearing, during which a majority appeared skeptical of its enforcement scheme that encourages citizens to sue anyone who aids or abets an unlawful abortion for the chance at a $10,000 bounty. Many observers assumed the court would quickly move to put the law on hold, but it has not done so.

A decision in the Mississippi and Texas cases are expected by the end of the court’s term in June 2022.

The abortion rights battle at the Supreme Court comes as Republican-led states have enacted more than 100 new abortion restrictions so far this year, according to the Guttmacher Institute, a research organization that supports abortion rights.

Twenty-one states have laws in place that would quickly impose abortion bans in the event the Supreme Court overturns Roe.

Fourteen states plus Washington, D.C., have laws explicitly protecting access to abortion care, according to Guttmacher.

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