BOSTON (AP) — Oral arguments are set for Wednesday at the Supreme Court in a challenge of a Massachusetts law that regulates where anti-abortion protesters can gather and approach patients near clinics.

In the state, abortion protesters must stay at least 35 feet away from a clinic's entrance. They argue the restriction is an unconstitutional infringement on free speech. And they say they have little chance of reaching patients arriving at Planned Parenthood clinics by car.

Planned Parenthood workers and state officials say the buffer zone has reduced significantly the harassment of patients and clinic employees.

Marty Walz, president and CEO of Planned Parenthood League of Massachusetts, says before the restriction went into effect in 2007, protesters could stand next to the clinic entrance and force patients to squeeze by.

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