"The buffer zones burden substantially more speech than necessary to achieve the Commonwealth's asserted interests," Roberts said.
Massachusetts began looking for ways to protect abortion clinics after receptionists at two Planned Parenthood clinics in Brookline, Mass., were killed on Dec. 30, 1994, by John Salvi, a young man who later died in prison in an apparent suicide.
Roberts said that Massachusetts in McCullen v. Coakley showed only that the buffer is easier for police, not that doing away with it would make their job of protecting clinics impossible. He also found there had been no arrests or prosecutions for protests outside clinics since the 1990s.
"To meet the narrow tailoring requirement, however, the government must demonstrate that alternative measures that burden substantially less speech would fail to achieve the government's interests, not simply that the chosen route is easier," he wrote.
Massachusetts adopted the 35-foot buffer zone after officials decided a law similar to a Colorado one that was approved by the Supreme Court in 2000 was impractical. That law set up 8-foot "floating bubbles" around patients, with protesters within 100 feet of clinics required to keep their distance unless the women consented to talk to them.