The judge also found that the sidewalk counselors have still been effective in communicating their message despite the 35-foot barrier. They can be seen and heard by "both willing and unwilling listeners" and have been "successful in convincing a number of women not to have abortions."

The ruling may be appealed and the matter could eventually be taken up by the U.S. Supreme Court. Judge Tauro is the same federal district judge who found the federal Defense of Marriage Act unconstitutional in 2010.

James Driscoll, executive director of the Massachusetts Catholic Conference (MCC), said the bishops are "disappointed" in the buffer zone ruling.

"Aside from the First Amendment concerns, criminalizing the peaceful and non-obstructive use of the sidewalks is unnecessary, punitive and unfairly excessive," he said.

Last June, the MCC testified in favor of a proposed law that would repeal the buffer zone. On its website, the MCC points out that, "Federal case law already requires individuals entering a designated zone outside the entrances of health facilities to gain the consent of other individuals before approaching closer than eight feet to counsel against abortion." Massachusetts law also prohibits individuals from obstructing any entrances to medical facilities.

The buffer zone law "creates no-speech zones in areas traditionally regarded as open to the public precisely for the purpose of free expression and assembly," the MCC contends.

Anne Fox, president of Massachusetts Citizens for Life, said that the law shows an unfair preference for abortion clinics.

"Unfortunately, in our country right now, the regular rules do not apply to abortion clinics," she said. "Either a buffer zone is a good idea that should apply to all health facilities, or it isn't and should apply to none."

Such laws are currently active in two states in addition to Massachusetts -- Colorado, which has a 100-foot barrier, and Montana, which has a 36-foot buffer.

The justification often used for a buffer zone is the incidents of violence that sometimes occur at abortion clinics. Fox pointed out that anyone who physically harms or kills another has violated laws much more serious than the buffer zone law.

She said the law has pushed peaceful protesters to sidewalks in front of other businesses or in the middle of busy streets. This is an undue burden on sidewalk counselors, who are particularly important in the commonwealth because no informed consent laws exist.

Roderick Murphy, director of Problem Pregnancy in Worcester, said that sidewalk counselors -- who pray outside the Planned Parenthood directly across the street from the pregnancy resource center -- would be able to assist two to three times as many women if the buffer zone law were repealed.

"It does affect the babies that are born," he said. "We have a much more difficult time speaking to women about abortion alternatives."