The Supreme Court on Friday agreed to hear its first major abortion case since 2007, one that has the potential to affect millions of women and to revise the constitutional principles governing abortion rights.
The court's decision will probably arrive in late June, as the presidential campaign enters its final stretch, thrusting the divisive issue of abortion to the forefront of public debate. Other major rulings — on affirmative action, public unions, contraception coverage and possibly immigration — are also expected to land around then.
But it is the new abortion case, however it is decided, that is likely to produce the term's most consequential and legally significant decision. Many states have been enacting restrictions that test the limits of the constitutional right to abortion established in 1973 in Roe v. Wade, and a ruling in the new case, from Texas, will enunciate principles that will apply in all of them.
The case may turn out to be the third installment in a legal trilogy on the scope of the constitutional right to abortion, one that started with Roe and continued in 1992 with Planned Parenthood v. Casey.
The Casey decision said states may not place undue burdens on the constitutional right to abortion before fetal viability. Undue burdens, it said, included "unnecessary health regulations that have the purpose or effect of presenting a substantial obstacle to a woman seeking an abortion."
Justice Anthony M. Kennedy helped write the controlling opinion in Casey, and his vote will almost certainly be crucial in the new case, Whole Woman's Health v. Cole, No. 15-274. The future of abortion rights in the United States probably rests almost entirely in his hands, given the deadlock on the court between conservatives and liberals.
The case is a challenge to a Texas law that would leave the state with about 10 abortion clinics, down from more than 40. Such a change, the abortion providers who are plaintiffs in the case told the justices, would have a vast practical impact.
"Texas is the second-most-populous state in the nation — home to 5.4 million women of reproductive age," they wrote in their brief urging the court to hear the case. "More than 60,000 of those women choose to have an abortion each year."
The case concerns two parts of a state law that imposes strict requirements on abortion providers. It was passed by the Republican-dominated Texas Legislature and signed into law in July 2013 by Rick Perry, the governor at the time.
One part of the law requires all clinics in the state to meet the standards for "ambulatory surgical centers," including regulations concerning buildings, equipment and staffing. The other requires doctors performing abortions to have admitting privileges at a nearby hospital.
Officials in Texas said the contested provisions were needed to protect women's health. Abortion providers responded that the regulations were expensive, unnecessary and intended to put many of them out of business.
The measures were modest and sensible, Ken Paxton, Texas' attorney general, said in a statement Friday.
"The state has wide discretion to pass laws ensuring Texas women are not subject to substandard conditions at abortion facilities," Paxton said. "The advancement of the abortion industry's bottom line shouldn't take precedence over women's health."
Nancy Northup, president of the Center for Reproductive Rights, which brought the Texas challenge, said officials in Texas had used "deceptive laws and regulatory red tape" to block access to abortion.
"Playing politics with women's health isn't just wrong," she said in a statement. "It's dangerous for many women who will have no safe and legal options left where they live, and may be forced to take matters into their own hands."
Parts of the law not at issue before the Supreme Court have caused about half of the state's 41 abortion clinics to close. If the contested provisions take effect, the challengers' brief said, the number of clinics would again be halved.
Amy Hagstrom Miller, president of Whole Woman's Health, the lead plaintiff, said that "would have devastating effects on women and families around the state."
The remaining clinics would be clustered in four metropolitan areas: Austin, Dallas-Fort Worth, Houston and San Antonio.
"There would be no licensed abortion facilities west of San Antonio," the challengers' brief said. The only clinic south of San Antonio, in McAllen, it added, would have "extremely limited capacity."
In urging the Supreme Court to decline the case, Paxton quoted from an earlier opinion. The justices, Paxton said, should not turn themselves into "the country's ex officio medical board with powers to approve or disapprove medical and operative practices and standards throughout the United States."
The lower courts are divided over whether they should accept lawmakers' assertions about the health benefits of abortion restrictions at face value or investigate to determine whether the assertions are backed by evidence.
In June, the 5th U.S. Circuit Court of Appeals, in New Orleans, largely upheld the contested provisions of the Texas law, using the more deferential approach. A panel of the court ruled that the law, with minor exceptions, did not place an undue burden on the right to abortion.
The court said women in West Texas could obtain abortions in New Mexico, a ruling at odds with one from a different panel of the same court that said Mississippi could not rely on out-of-state abortion clinics in defending a law that would have shut down the state's only clinic.
The appeals court declined to grant the challengers a stay, but the Supreme Court temporarily blocked the ruling later that month pending its own decision in the case. The vote was 5-4, with Kennedy joining the court's liberal wing to form a majority. Chief Justice John G. Roberts Jr. and Justices Antonin Scalia, Clarence Thomas and Samuel A. Alito Jr. voted to deny the stay.