The court voted 5-4 to deny an emergency appeal from abortion providers and others that sought to block enforcement of the law that went into effect Wednesday. But the justices also suggested that their order likely isn’t the last word on whether the law can stand because other challenges to it can still be brought.

The Texas law, signed by Republican Gov. Greg Abbott in May, prohibits abortions once medical professionals can detect cardiac activity, usually around six weeks and before many women know they’re pregnant.

It is the strictest law against abortion rights in the United States since the high court’s landmark Roe v. Wade decision in 1973 and part of a broader push by Republicans nationwide to impose new restrictions on abortion. At least 12 other states have enacted bans early in pregnancy, but all have been blocked from going into effect.

The high court’s order declining to halt the Texas law came just before midnight Wednesday. The majority said those bringing the case had not met the high burden required for a stay of the law.

“In reaching this conclusion, we stress that we do not purport to resolve definitively any jurisdictional or substantive claim in the applicants’ lawsuit. In particular, this order is not based on any conclusion about the constitutionality of Texas’s law, and in no way limits other procedurally proper challenges to the Texas law, including in Texas state courts,” the unsigned order said.

Chief Justice John Roberts dissented along with the court’s three liberal justices. Each of the four dissenting justices wrote separate statements expressing their disagreement with the majority.

Roberts noted that while the majority denied the request for emergency relief “the Court’s order is emphatic in making clear that it cannot be understood as sustaining the constitutionality of the law at issue.”

The vote in the case underscores the impact of the death of the liberal Justice Ruth Bader Ginsburg last year and then-president Donald Trump’s replacement of her with conservative Justice Amy Coney Barrett. Had Ginsburg remained on the court there would have been five votes to halt the Texas law.

Justice Sonia Sotomayor called her conservative colleagues’ decision “stunning.” “Presented with an application to enjoin a flagrantly unconstitutional law engineered to prohibit women from exercising their constitutional rights and evade judicial scrutiny, a majority of Justices have opted to bury their heads in the sand,” she wrote.

Texas lawmakers wrote the law to evade federal court review by allowing private citizens to bring civil lawsuits in state court against anyone involved in an abortion, other than the patient. Other abortion laws are enforced by state and local officials, with criminal sanctions possible.

In contrast, Texas’ law allows private citizens to sue abortion providers and anyone involved in facilitating abortions. Among other situations, that would include anyone who drives a woman to a clinic to get an abortion. Under the law, anyone who successfully sues another person would be entitled to at least $10,000.

In her dissent, Justice Elena Kagan called the law “patently unconstitutional,” saying it allows “private parties to carry out unconstitutional restrictions on the State’s behalf.” And Justice Stephen Breyer said a “woman has a federal constitutional right to obtain an abortion during” the first stage of pregnancy.

After a federal appeals court refused to allow a prompt review of the law before it took effect, the measure’s opponents sought Supreme Court review.

In a statement early Thursday after the high court’s action, Nancy Northup, the head of the Center for Reproductive Rights, which represents abortion providers challenging the law, vowed to “keep fighting this ban until abortion access is restored in Texas.”

“We are devastated that the Supreme Court has refused to block a law that blatantly violates Roe v. Wade. Right now, people seeking abortion across Texas are panicking — they have no idea where or when they will be able to get an abortion, if ever. Texas politicians have succeeded for the moment in making a mockery of the rule of law, upending abortion care in Texas, and forcing patients to leave the state — if they have the means — to get constitutionally protected healthcare. This should send chills down the spine of everyone in this country who cares about the constitution,” she said.

Texas has long had some of the nation’s toughest abortion restrictions, including a sweeping law passed in 2013. The Supreme Court eventually struck down that law, but not before more than half of the state’s 40-plus clinics closed.

Even before the Texas case arrived at the high court the justices had planned to tackle the issue of abortion rights in a major case after the court begins hearing arguments again in the fall. That case involves the state of Mississippi, which is asking to be allowed to enforce an abortion ban after 15 weeks of pregnancy.

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