The Louisiana law - passed in 2014 but never allowed to go into effect - requires any physician providing abortion services to have admitting privileges at a hospital within 30 miles of the procedure.
Even Louisiana acknowledges that the requirement is virtually identical to a Texas law that the Supreme Court voted 5 to 3 to strike down in 2016. The court said the admitting privilege requirement, along with additional standards for clinics, "provides few, if any, health benefits for women, poses a substantial obstacle to women seeking abortions, and constitutes an 'undue burden' on their constitutional right to do so."
But a panel of the conservative U.S. Court of Appeals for the 5th Circuit, which covers Louisiana, Texas and Mississippi, upheld the Louisiana law in a 2-to-1 vote. The full court, considered one of the most conservative of the regional appeals courts, voted not to reconsider that decision.
Dissenting judges practically accused their colleagues of trying to set up the Supreme Court to reconsider its Texas decision, Whole Woman's Health v. Hellerstedt, with one saying the appeals court relied on "strength in numbers rather than sound legal principles in order to reach their desired result in this specific case."
Another said the majority had simply ignored the Supreme Court precedent.
"I am unconvinced that any justice of the Supreme Court who decided Whole Woman's Health would endorse our opinion," Judge Stephen Higginson wrote in his dissent.
"The majority would not, and I respectfully suggest that the dissenters might not either. As Justice (Clarence) Thomas wrote, 'unless the Court abides by one set of rules to adjudicate constitutional rights, it will continue reducing constitutional law to policy-driven value judgments until the last shreds of its legitimacy disappear.' "
Higginson's theory will be put to the test quickly. The law is scheduled to go into effect Feb. 4 unless the Supreme Court intervenes.
The Whole Woman's Health decision was the court's most important one on abortion in a quarter-century. But it was decided by a very different Supreme Court, in the wake of the death of conservative Justice Antonin Scalia.
Justice Anthony Kennedy joined the court's liberals to strike down the Texas provisions. Chief Justice John Roberts, Justice Samuel Alito and Thomas were in dissent.
But those three have since been joined by President Donald Trump's choices, Justice Neil Gorsuch and Brett Kavanaugh, both of whom were supported by antiabortion activists who said they hoped the new court majority might one day overturn the fundamental right to abortion the court advanced in Roe v. Wade.
Jennifer Dalven, director of the American Civil Liberties Union's Reproductive Freedom Project, said laws like Louisiana's provide a way to sharply limit the availability of abortion without taking on the precedent of Roe.
"If the Supreme Court lets a law like this take effect, it sends a very dangerous signal to state legislators" that the way to limit abortion is to pass restrictive laws on the operation of clinics and doctors who provide the service.
But Louisiana tells the Supreme Court that the challengers have not pointed to mistakes in the fact-specific majority opinion, and that allowing the law to go into effect would not create an emergency that warrants the high court's intervention.
"All of Plaintiffs' claims of irreparable harm rest on the premise that Louisiana will move aggressively to enforce the challenged law, potentially shutting down abortion clinics overnight," Louisiana Attorney General Jeff Landry wrote. "But that is not correct. Louisiana envisions a regulatory process that begins, logically, with collecting information from Louisiana's abortion clinics and their doctors."
Judge Jerry Smith, writing for the two-member appeals court majority, said that he was bound by the Supreme Court's decision in Whole Woman's Health and that he took a painstaking look at the details.
"Unlike in Texas, the (Louisiana law) does not impose a substantial burden on a large fraction of women," he concluded.
He said the closing of some clinics in Louisiana, as opposed to Texas, would not dramatically increase driving distances, and that it was easier for doctors in Louisiana to procure admitting privileges. He said that "at most, only 30 percent of women" seeking abortions in Louisiana would be affected.
"The record here indicates that the admitting-privileges requirement performs a real, and previously unaddressed, credentialing function that promotes the wellbeing of women seeking abortion," he wrote.
Still, he acknowledged, the benefits are "not huge." In a footnote, he wrote that "the state did not provide any instance in which a worse result occurred because the patient's abortion doctor did not possess admitting privileges."
Challengers of the law say that is because abortions performed in Louisiana clinics seldom result in hospitalization: 0.05 percent for abortions in the first trimester and about 1 percent in the second trimester.
The panel rejected a lower court's finding that the law would affect about 70 percent of women seeking abortions in the state. After a trial, that judge found that two of the remaining three abortion clinics in the state would have to close because they would not have a doctor who could obtain admitting privileges.
The only remaining clinic would "be unable to meet the annual demand for roughly 10,000 abortions in the state."
"The 5th Circuit brazenly ignored recent U.S. Supreme Court precedent squarely on point," said Nancy Northup, president and CEO of the Center for Reproductive Rights, which is representing the challengers and also successfully fought the Texas law. "There is no way this law can stand under the Supreme Court ruling in Whole Woman's Health."
The Supreme Court seems to have taken a low-key approach to this term, after an unwelcome moment in the political spotlight during the partisan brawl over Kavanaugh's nomination.
But cases such as this one often forces its hand. The court is not being asked to consider the merits of the case now, but whether the law should be put in place while it is appealed.
What it decides about the stay will be closely watched by both sides. Abortion-rights supporters will view a decision to allow the law to go into effect, as Northup indicated, as a troubling sign that the court is no longer willing to stand by its precedent in the Texas case, decided less than three years ago.
Those opposed to abortion, on the other hand, would be disappointed by a Supreme Court reinforced with conservatives stepping in to stop a law that an appeals court has approved.
The case is June Medical Services v. Gee.