WASHINGTON -- The Supreme Court yesterday ended a 20-year old lawsuit against militant anti-abortion groups, ruling unanimously that their use of "physical violence" outside clinics did not violate the anti-racketeering laws.

The decision marked the third time this case had been decided by the Supreme Court, and this time, they made sure it would be the last.

The effect of the ruling will be limited, however, because a federal law enacted in 1994 makes it illegal to block the entrances to an abortion clinic.

Lori Kolavic, of the Allegheny Reproductive Health Center in Pittsburgh's East Liberty neighborhood, did not necessarily see the decision as an anti-choice action. "It's not something we need to get up in arms about," she said.

"There is an anti-choice fervor" under the Bush administration that is anti-woman, Ms. Kolavic asserted, and "while this decision may embolden some protesters, it is not a blow to pro-choice."

The decision is a narrow, technical one that is "disappointing," said Sue Frietsche with the Women's Law Project in Pittsburgh, but it does not dismantle protections that Congress has initiated for women and physicians at health clinics.

The Supreme Court ruling, she said, "is not sending a green light to anyone to think they should get away with assault or menacing at the clinics."

Mary Lou Gardner of Penn Hills has been a member of People Concerned with the Unborn Child since 1974, when she attended the first national March for Life in Washington, D.C. She hailed yesterday's high-court decision for protecting protesters' rights. "We're demonstrating, not racketeering," she said.

The lawsuit that ended yesterday began during an era of abortion-clinic bombings in the 1980s. At the same time, anti-abortion groups such as Operation Rescue employed "human blockades" to try to stop pregnant patients from entering clinics.

Searching for a legal weapon to combat such tactics, the National Organization for Women sued Operation Rescue and its leaders for violating the federal anti-racketeering law. This law incorporates other federal measures, including the laws against robbery and extortion.

The Supreme Court allowed this suit to go forward in 1994, and a jury in Chicago ruled that the protesters had used force and, on occasion, violence to prevent patients and staff from entering clinics. A judge assessed damages against Operation Rescue and issued a nationwide order forbidding its members from blocking clinics.

Three years ago, the Supreme Court appeared to reverse course. It ruled that the protesters did not engage in "extortion" when they blocked clinics because they were not seeking to take over these businesses. The justices sent the case back to Chicago, apparently assuming it was over. But a U.S. appeals court there said that because violence was used on several occasions, the lawsuit could continue.

In yesterday's ruling, the justices said they meant to end the case entirely. Because the protesters had not engaged in extortion, they did not violate the anti-racketeering law in the first place.

While the lawsuit was languishing in the lower courts, Congress passed the Freedom of Access to Clinic Entrances Act of 1994. It makes it a crime to block health clinics, and it also permits clinic operators to sue if their rights under the law are violated.

Moreover, Pittsburgh City Council in December passed an ordinance creating a buffer zone that requires protesters to stay 15 feet from entrances to medical centers and at least 8 feet from persons or personnel who are using the centers.

Mrs. Gardner, said that when pro-life groups such as her People Concerned with the Unborn Child gather in front of reproductive health centers, they only want to share alternatives with young women and convince them of the humanity of the unborn. "It's not racketeering. We have nothing monetary to gain," she said, and yesterday's court decision "takes away the fear of being sued."

Helen Cindrich, who belongs to the same anti-abortion group, said the ruling means that people won't be afraid of protesting. She once was arrested for protesting outside an abortion physician's home and was sued, as was her husband because she drove his car to the protest.

When the plaintiffs linked her protest to racketeering, she said, that was like "finding a needle in a haystack and trying to build a house on it."