As she makes her nursing home rounds, as she has for 28 years, Sister Constance Veit gently grasps frail hands, steers wheelchairs with no-nonsense grace and doles out cheery compliments to those in her care. But the moment the nun gets behind the closed door of a conference room, her demeanor hardens. This is a sister at war.

On Wednesday, Veit will be just a few miles from the Little Sisters of the Poor facility where she works in Northeast Washington — and a world away. She will be seated in her habit in the U.S. Supreme Court, a striking representative of the religious organizations fighting the White House health care law because of its requirement that employers cover contraception.

The Little Sisters of the Poor, who run a nursing home chain, are among seven plaintiffs in a case called Zubik v Burwell. While the order isn’t the name on the case, it has become the sympathetic face of it. In the fall, Pope Francis even brought his popularity to bear on the part of the nuns, when he made an unannounced visit to the Sisters in the District.

But advocates ranging from prominent nuns to the ACLU have said the way the contraception mandate already works requires no capitulation on the nuns’ part. In fact, they argue, changing the law would harm the poor whom the nuns claim to support, by denying thousands of women access to a covered service.

The case could impact thousands of employees who rely on insurance plans issued by their faith-based employers. It also could shift the tone of the ongoing fight over how to balance religious freedom with rights such as birth control access.

The Affordable Care Act requires that most health insurance plans provide contraceptives free of charge. Under Obamacare, the government allows religious organizations like the Little Sisters of the Poor to sign a document saying they will not pay for contraceptive coverage for their employees, thus letting the government ensure that those employees get contraceptive coverage separately.

But the Little Sisters of the Poor and the six other organizations involved in this case will tell the Supreme Court Wednesday that they find even signing that opt-out document is prohibited by their religion.

“What this form is, it’s not an opt-out. It’s an opt-in. It’s a permission slip by which we would be giving the government permission to go into our plan,” Veit said. “By signing that form, we’re authorizing the government to go in and take over our healthcare plan.”

Lori Windham, an attorney at the Becket Fund for Religious Liberty which represents the nuns, argued, “This is actually using the sisters’ authorization to come in and add something to their healthcare plan.”

Asked about the case earlier, White House press secretary Josh Earnest argued that the opt-out form strikes the right balance between women’s right to healthcare and organizations’ right to religious expression. “The policy we have in place appropriately balances the need of millions of Americans to have access to birth control, while also protecting the right of religious freedom that is protected in the Constitution,” he said.

If the nuns lose their case and do not comply with the law, they face substantial fines. Still, Veit says, “I can’t imagine a scenario where we would sign the form.”

While the nuns themselves take a vow of chastity, the Little Sisters of the Poor is an employer, meaning they provide health care to employees who might not be Catholic.

The 10 nuns who work at the Jeanne Jugan Residence, the sisters’ Washington home for elderly people with significant financial need, supervise the institution. But most of the work is done by employees outside the order.

Veit, who serves as activities director and vocations director, said the sisters employ almost 100 people — mostly nursing assistants — at their Washington home, and about 2,500 people in 26 other homes nationwide.

Veit says that anyone who takes a job at the Jeanne Jugan Residence knows about the sisters’ beliefs. But the sisters are careful not to question employees about their private lives, including their decisions on birth control.

Presumably much of their workforce, even Catholic employees, do use contraception. Surveys have found that 68 percent of sexually active Catholic women in the U.S. are using birth control pills, IUDs or sterilization. And large numbers of women use birth control pills for medical purposes that have nothing to do with preventing pregnancy.

William D’Antonio, a senior fellow at Catholic University of America who studies Catholics in the United States, said that the majority of American Catholics consistently say in surveys that they do not see contraception as sinful.

He said that most of the major theologians whose opinion he looks for on Catholic issues have not spoken up in favor of the Little Sisters of the Poor and the other plaintiffs in this case.

“I just think it’s a poor case,” D’Antonio said of the nuns’ contention that they cannot in good faith sign the opt-out form. “Somehow they’re being called upon to commit a material evil themselves? That seems to me that that’s rather an extraordinary position.”

Without insurance coverage, a woman might pay up to $50 a month, or $600 a year, for birth control pills. D’Antonio pointed out that the cost would likely be high for many of the nursing assistants who work at the sisters’ homes.

“The people who are working for them, they’re hardly the upper-middle class. They’re people who need all the healthcare they can get, and that includes being able to protect themselves from unwanted pregnancy,” he said. “It seems extraordinary that the Sisters of the Poor — who deal with the poor — should deny them that right.”

Veit said she realized the people who work at her nursing home might need to pay for contraception if the nuns have their way. “I would concede that maybe in some cases this would make it harder for a woman to get contraception. Okay, I recognize that,” she said. “I would hope that in an environment where we respect each other’s convictions, that would be one step that a woman who respects our convictions would make.”

The Little Sisters of the Poor’s nursing home in the District, in a neighborhood saturated with Catholic institutions — next door to the St. John Paul II National Shrine, across the street from Catholic University of America, around the corner from the Basilica of the National Shrine of the Immaculate Conception — showed no signs on Monday that it is at the center of a national debate.

It’s a quiet religious institution, wrapped up in its day-to-day duty of caring for the elderly and right now in the pre-Easter season of Holy Week.

A deacon leading a Bible study before the daily 11 a.m. Mass in the nursing home’s chapel asks a circle of 10 residents, “What is God telling us by that, washing the feet?” and the women chime in with responses. “We’re all one.” “Humility.”

Veit is handing out roses she has twisted from the Palm Sunday fronds. The first one goes to Martha De Filippi, who is 93 years old and says she has lived at the home for 17 years, moving from its independent living wing to assisted living to nursing care.

Then to Betty Letoile, also in her 90s, who cannot remember all her daughters’ names and has a note pinned on her wall reminding her to expect the arrival of a great-grandchild. But Letoile proudly tells Veit of her son Ken, a Dominican friar: “Father Ken. He’s a wonderful person. He does so much for everyone.” And she remembers the lyrics to an old Bing Crosby song. Veit crouches by her wheelchair, and they sing together.

Then Veit steps away from the nursing floor. The subject turns to the Affordable Care Act. And in an instant, her tone is totally transformed.

The gentle caregiver of the nursing floor becomes a crusader. She cites facts and figures. She decries those who oppose her. “It’s a matter of the principle, of having to be involved in something we find morally reprehensible,” she says.

She is impressed by the weightiness of her order’s case making it all the way to the Supreme Court. “It’s certainly kind of an awesome, previously unimaginable situation. And this is all happening during Holy Week,” Veit said. “This is happening on the verge of us entering into the holiest days of the year. I can’t go into it without being cognizant of what our Lord went through during these days.”

On Wednesday morning, she expects nuns of many orders to join her at the Supreme Court wearing their many-colored habits, all crusading together toward the same goal.

This post has been updated.

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