WASHINGTON — The Supreme Court changed course on abortion Wednesday, upholding a national ban on a midterm method of ending pregnancies. The decision clears the way for states to pass new laws designed to discourage women from having abortions.
In a 5-4 ruling applauded by antiabortion forces, the court said the "government has a legitimate and substantial interest in preserving and promoting fetal life." In 2000, the court, also by a 5-4 margin, struck down a nearly identical state law on the grounds that it could force some women to undergo riskier surgery during the fourth or fifth month of pregnancy. But the retirement of Justice Sandra Day O'Connor in 2005 and President Bush's appointment of Samuel A. Alito Jr. to succeed her tipped the balance the other way.
It was the first time the court upheld a ban on an abortion procedure. Though Wednesday's opinion does not overturn Roe vs. Wade, the 1973 decision establishing a constitutional right to abortion, the majority said it was prepared to uphold new restrictions on doctors who perform them and women who seek them.
Justice Anthony M. Kennedy, speaking for the court, said that the government may not forbid abortion outright but that it "may use its voice and its regulatory authority" to dissuade women from ending pregnancies. The ban on what opponents call "partial-birth" abortions will "encourage some women to carry the infant to full term, thus reducing the absolute number" of such abortions, he added.
Chief Justice John G. Roberts Jr. and Justices Antonin Scalia, Clarence Thomas and Alito joined Kennedy's opinion. In a separate statement, Thomas and Scalia said they would vote to overrule Roe vs. Wade entirely.
The decision is likely to elevate the abortion issue in the 2008 presidential campaigns. Two of the court's strongest supporters of the right to abortion are also its oldest: John Paul Stevens will be 87 on Friday, and Ruth Bader Ginsburg is 74. The next president might have to nominate one or more new justices.
Ginsburg, the court's only woman, called Wednesday's decision "alarming."
It "cannot be understood as anything other than an effort to chip away at a right declared again and again by this court," she said.
She said this dispute was about how, not whether, abortions would be performed during the second trimester. Despite Kennedy's talk of "promoting fetal life," the ban on the procedure "targets only a method of abortion," she said. "The woman may abort the fetus, so long as her doctor uses another method, one her doctor judges less safe for her."
