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Fetal Viability and the Fate of Abortion Laws in U.S.

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The concept of “fetal viability” is at the center of the U.S. Supreme Court case that could undercut or even eliminate the constitutional right to abortion. Under the court’s precedents, states can’t impose significant restrictions on abortion access before the point of fetal viability. Defending its attempt to ban abortion starting at 15 weeks of pregnancy, Mississippi is asking the court to discard the fetal viability line and give states broad power to restrict abortion at earlier stages. About 7% of abortions in the U.S. -- or about 36,000 a year, using data for 2019 -- take place in the 15th week or later, meaning they could become outlawed in many states. According to a leaked draft of a majority opinion, published by Politico, the court is poised to overturn precedent and side with Mississippi. 

1. What is fetal viability?

In short, it’s the point at which a fetus is capable of living outside the womb with medical intervention. Exactly when it occurs requires a case-by-case determination. The most premature baby known to have survived was born (in 2020) at 21 weeks, 2 days in 2020, but doctors say fetal viability generally occurs a bit later than that. In the 1992 Planned Parenthood v. Casey case, the Supreme Court said viability tended to be around 23 to 24 weeks but could shift toward an earlier date as medical technology improved. 

2. Why does viability matter in abortion cases?

The Supreme Court itself made fetal viability a pivotal issue. In its 5-4 decision in the Casey case, the court reaffirmed the core abortion right established in 1973 in Roe v. Wade but modified the test for assessing the constitutionality of state regulation. Until the point of viability, the five-justice majority ruled, the state can’t impose an “undue burden” on the right to end a pregnancy. In the two decades since Casey, the court has let states impose such requirements as waiting periods and parental consent rules for minors but never a pre-viability ban on abortion, as Mississippi is seeking to do. 

3. What does Mississippi want?

In 2018, the state’s legislature voted to ban abortions after the 15-week mark, except in cases of severe fetal abnormality or major health risk to the mother. The proposed law was challenged by the state’s only abortion facility, the Jackson Women’s Health Organization, and deemed unconstitutional by a federal district judge and federal appeals court. The state appealed to the Supreme Court, arguing that viability is “not an appropriate standard for assessing the constitutionality” of abortion laws. Mississippi says at the minimum, the court should drop the viability standard and let states restrict abortion at earlier stages in pregnancy.

4. What would eliminating the viability test mean?

In Mississippi, the immediate effect would be minimal, since the Jackson Women’s Health Organization provides abortions only until the 16-week mark. More broadly, however, the effect could be immense. During arguments on Dec. 1, the court showed little interest in replacing viability with a new legal test, and even abortion-rights advocates didn’t suggest an alternative. So a ruling in Mississippi’s favor could clear the way for much earlier prohibitions, by Mississippi and other states with Republican-led governments. More than 20 states have laws already on the books, ready for the day Roe v. Wade is rolled back, that would ban some or all pre-viability abortions. Mississippi itself passed a separate, more stringent ban on abortions after six weeks, which so far has been blocked in court, and it is one of 12 states with trigger laws that would automatically kick in if Roe is overturned and bar almost all abortions.

5. Will the viability standard survive?

Judging from the Dec. 1 argument, all six of the court’s Republican appointees were ready to jettison the viability line. That included Chief Justice John Roberts, the lone conservative who has occasionally backed abortion access. Roberts said viability was a standard the U.S. shared with China and North Korea -- prompting abortion-rights advocate Julie Rikelman to counter that Canada and most European countries allow abortion until that point as well. The bigger question is whether the court will go further and overturn Roe and Casey entirely, something questioning from the other conservatives suggested was a possibility. The leaked initial draft was written by Justice Samuel Alito and circulated in February. It was supported by at least five of the nine justices, according to Politico, which noted, however, that things could change before the court issues its ruling, expected by July.

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