FALLS CHURCH, Va. — On a recent bright Saturday morning, Ruby Nicdao, a petite woman in a neon visor, stood outside the Falls Church Healthcare Center hoping to save women from entering what she called the “devil’s playpen.”

Spotting a young woman walking across the parking lot to the doors of the abortion clinic, Nicdao lifted a small orange traffic cone to her mouth and called out, “Excuse me, ma’am. Are you pregnant? We can help you.”

In January the Supreme Court heard arguments in the case of McCullen v. Coakley, regarding a Massachusetts law that establishes a 35-foot buffer zone around entrances of abortion clinics to protect their employees and patients. Lead plaintiff Eleanor McCullen, who regularly makes appeals to women outside the Planned Parenthood clinic in Boston, says the law violates her First Amendment rights, while abortion providers contend buffer zones are necessary to ensure their safety as well as patients’ access to clinics.

The issue — which could see a judgment come down as soon as Wednesday — has turned into one of the most important abortion cases to come before the Supreme Court in years. The scene outside Falls Church illustrates just how tenuous the balance is between the two sides and — if McCullen’s legal team wins her case — offers a glimpse of a future for other parts of the U.S. if buffer zone laws are deemed unconstitutional.

Nicdao’s efforts to counsel women, as she calls it, are thwarted not by a buffer zone law — none exists in Virginia — but by a large parking lot in front of the main entrance that is private property. Using the physical bounds of the clinic to create a shield is just one measure that Rose Codding, owner of the Falls Church center, has implemented since opening in 2002 to keep her staff and patients free from what she calls harassment. Protesters are first warned if they enter the parking lot and may be arrested for trespassing if they ignore the warning.

“The police here are very responsive,” said Codding. “It took about three years to set up the relationship, but the protesters who come here know there are limits.”

In addition, she uses clinic escorts from the Washington Area Clinic Task Force. They stand in purple vests near the entrance, ready to be a welcoming face and make the experience more comfortable. These efforts seem to maintain a relative calm outside the building, even as the parking lot’s edge serves as a line of battle in a seemingly unending war that continues to unfold across the country.

Nicdao was one of several protesters on this particular morning who fanned out along the sidewalk in front of the parking lot to better reach potential patients. Two young women clutching rosaries prayed together at one end while several men paraded up and down the street, their fists pumping slightly to better show off large signs that read, “Abortion kills.”

Bob Gahl, the first demonstrator to arrive, viewed the measures that Codding has set up as an infringement on his work. Wearing a faded red baseball cap and speaking in a slow drawl, he said he tried to get women into a van parked nearby where there was a sonogram machine set up so they could hear the heartbeat of their fetuses. But he lamented the fact that he cannot cross into the parking lot to speak to women because he will face arrest. “The local police are on the side of the abortion clinic,” said Gahl.

In other cities without buffer zones, however, the scene is not always so calm. And this is one of the main arguments of proponents of buffer zone laws.

A September 2013 National Abortion Federation (NAF) survey of its members found that 51 percent of facilities with buffer zones reported a decrease in criminal activity and 75 percent reported increased access to clinics. Vicki Saporto, president of the NAF, describes the laws as “a commonsense approach to the threats, intimidation and violence that remain a real threat today.”

This may be one reason the laws have gained popularity. New Hampshire passed legislation in early June establishing 25-foot zones around clinics, and the city council in Englewood, New Jersey, authorized eight-foot zones in March.

Mary Lou Greenberg runs the Choices abortion clinic in Jamaica in the New York City borough of Queens. It’s the scene of regular Saturday protests, but Choices has no large parking lot or legislation to create a buffer zone.

She said that despite regular appeals to law enforcement, there is little that can be done to mitigate the protesters because of First Amendment protections. While Greenberg also uses clinic escorts, she said it doesn’t prevent women from feeling intimidated.

“They actively follow the women that come here and try to get in front of them or between them and the door,” she said. “It’s really just this gauntlet of vitriol and hate.”

But Troy Newman, who runs Operation Rescue in Kansas, an anti-abortion organization with which Ellen McCullen is affiliated, is adamant that protesters’ speech should be protected.

“The First Amendment doesn’t give you the right to feel good or to be safe from criticism,” he said. “It guarantees our right to the freedom of political speech and particularly religious speech.”

Lawyers for McCullen are seeking not just to have the Massachusetts law overturned but to have any regulation of the kind nationwide deemed unconstitutional. If this happens, it may make the makeshift protections that have been implemented at Falls Church more common.

Codding says she’s watching the decision closely, since even though it may not affect laws in Virginia, it is an indicator of what protections are feasible for abortion providers around the country.

“The McCullen decision is important for all of us to be able to set up zones that are free from verbal harassment,” she said.

At Falls Church, Codding has ensured that her employees and patients can reach the clinic with ease. As a bulwark in the fight for access to abortion since the Roe v. Wade decision, she said, she has been the target of threats and intimidation for years and doesn’t want to take unnecessary chances with her staff.

“I still check under my car for bombs before I get in,” she said.

Employees use a buddy system to enter and leave the building and are told to change into their scrubs after they get inside so that protesters can’t easily identify them as clinic employees. They take turns filling out a daily log of the number of protesters and any incendiary actions, which are later reported to the NAF.

“Of course it affects me, being told I’m going to hell every day,” said Carla Turcio, a counselor at the center. “But really it affects my patients, and that’s what I’m most concerned about.”