The Biden administration told the Supreme Court on Wednesday that intervention is required to keep Texas from “nullifying” the constitutional right to abortion that the court established nearly 50 years ago.

The brief was submitted in advance of Monday’s hastily scheduled hearing on the Texas law that has virtually shut down abortion within the state’s borders. Texas, the federal government, abortion providers and individual citizens who want to enforce the law called S.B. 8 each made their cases.

“Texas insists that the Court must tolerate the state’s brazen attack on the supremacy of federal law because S.B. 8’s unprecedented structure leaves the federal judiciary powerless to intervene,” acting solicitor general Brian H. Fletcher wrote in the government’s brief. “If Texas is right, no decision of this Court is safe.”

Texas countered that its law may be challenged in state court when it is enforced, but rejected the notion the federal government has a role to play in trying to stop it at this point.

“Texas does not cause the United States injury by the mere existence of an allegedly unconstitutional state law that may affect private parties,” Texas Attorney General Ken Paxton said in his brief.

“Not even the United States can obtain an advisory opinion on the constitutionality of Texas’s law by suing Texas.”

The Supreme Court allowed a Texas law banning abortion past six weeks to remain in effect. Other conservative states may adopt similar measures going forward. (Blair Guild/The Washington Post)

The cases the court will hear Monday raise complicated legal procedure questions precisely because S.B. 8 was drafted to avoid federal court review. Its effect is to ban abortions after about six weeks — before many know they are pregnant. But its enforcement structure was designed to keep it from being stopped by federal judges before it can go into effect — the fate of other state laws prohibiting abortion earlier than Supreme Court precedent allows.

Abortion providers said the court’s attention is warranted because the technique will quickly spread.

“If Texas gets away with this ploy, the constitutional right to abortion will be the first but certainly not the last target of States unwilling to accept federal law with which they disagree,” said the brief filed by Whole Women’s Health, which has clinics in the state.

The Texas case is only the leadoff in what could be a momentous term for reproductive rights at the Supreme Court. The justices on Dec. 1 will consider a Mississippi law that bans most abortions after 15 weeks.

That case, unlike the Texas law, will have implications for Roe v. Wade and Planned Parenthood v. Casey, the cases that, respectively, first established a constitutional right to abortion in 1973 and reaffirmed it in 1992.

In United States v. Texas and Whole Women’s Health v. Jackson, both to be argued Monday, the justices will examine unique enforcement policy for the law’s prohibition on abortions after cardiac activity is noted in the embryo, as early as about six weeks. There is no exception for rape or incest, and the abortion patient cannot be sued.

Usually in challenging abortion restrictions, opponents seek to enjoin government officials from enforcing laws that violate the constitutional protections the Supreme Court has recognized. Numerous state laws that would have banned previability abortions were struck by federal courts on those grounds.

But the Texas law is enforced by private citizens rather than the state government. Any individual can sue anyone who aids or abets a prohibited abortion. Successful lawsuits would result in an award of at least $10,000 to the person who filed the complaint.

When the Supreme Court considered a request from abortion providers to keep the state law from going into effect, the majority’s one-paragraph opinion cited the law’s “complex and novel” procedural questions and said it was not clear that abortion providers challenging the law were suing the proper defendants.

“Federal courts enjoy the power to enjoin individuals tasked with enforcing laws, not the laws themselves,” the majority wrote in allowing the law to go into effect. The majority consisted of Justices Clarence Thomas and Samuel A. Alito Jr., along with President Donald Trump’s three nominees, Neil M. Gorsuch, Brett M. Kavanaugh and Amy Coney Barrett. The group said the law presented “serious” constitutional questions.

The court’s three liberals — Justices Sonia Sotomayor, Stephen G. Breyer and Elena Kagan — said it was clear to them the law was, in Sotomayor’s words, “flagrantly unconstitutional.”

Chief Justice John G. Roberts Jr. provided a fourth vote for blocking the law, saying it required additional judicial scrutiny. “The statutory scheme before the court is not only unusual, but unprecedented,” he wrote. He would have allowed more time for courts to consider “whether a state can avoid responsibility for its laws in such a manner.”

After the suit brought by abortion providers was turned away, the Justice Department got involved, suing the state of Texas on behalf of those who it said were being denied their constitutional rights. A federal district judge agreed with the government. U.S. District Judge Robert L. Pitman halted the law, writing, “This court will not sanction one more day of this offensive deprivation of such an important right.”

Two days later, however, a panel of the U.S. Court of Appeals for the 5th Circuit overruled him and reinstated the law. It said it would consider the merits of the law in December. But the Supreme Court agreed to the request from abortion providers and the Justice Department not to wait for the 5th Circuit to rule on the merits.

The court did leave the law in effect, as it has been since Sept. 1.

In its brief Wednesday, the Justice Department counters Texas’s claim that those affected by the law can violate it and assert in state court that the law is unconstitutional because of the Supreme Court’s precedents.

“That path is not even theoretically available to pregnant women — whose rights S.B. 8 directly violates — because they cannot be sued under the law,” the Justice Department states. “And S.B. 8 is designed to ensure that the threat of enforcement suits deters providers from performing covered abortions altogether.”

But Texas counters that does not mean the federal government has a right to stand in their place.

Jonathan Mitchell, one of the law’s architects who represents private citizens wishing to bring suits, agreed in his brief to the court that the executive branch lacks authority.

“Congress has never authorized the United States to sue a state whenever it violates the constitutional rights of its citizens,” he writes.

He added: “What is deterring abortion providers is not the procedural structure of SB 8 or its threatened penalties, but the uncertain status of the right to abortion” given the court’s decision to take up the Mississippi case.