When the discussion turns to Opportunity Scholarships, it’s not hard to make Janet Nunn cry.

Not that I was trying.

Nunn is one of three clients working with the Institute for Justice to protect the Opportunity Scholarship program, which provides up to $4,200 a year to low-income families. The families use that money to send their children to the private schools of their choice.

“I do get emotional,” Nunn admits, tears flowing from her eyes. “I get real emotional because when you see where she was to where she’s at now, I am forever grateful — forever grateful.”

The “she” is Nunn’s granddaughter, Nariah. We’ll have more to say about her in a moment.

First, I should explain the circumstances that prompted me to send Nunn’s tear ducts into overdrive.

Five years ago, the N.C. Supreme Court ruled, 4-3, that the Opportunity Scholarship program complies with the state Constitution. Plaintiffs tied to North Carolina’s traditional public school establishment had challenged the program. They objected to low-income families using tax dollars to move their children out of traditional district schools that had failed to meet the children’s needs.

Once the state’s highest court signed off on the program, more and more qualified families signed up. Opportunity Scholarships now help more than 12,000 students across the state.

Now the program faces a new legal challenge.

The original complaint had argued that the very concept of Opportunity Scholarships violated the N.C. Constitution. The plaintiffs had mounted a so-called “facial challenge” to the scholarship law, arguing that Opportunity Scholarships never could meet state constitutional guidelines under any circumstances.

Having failed with that argument in 2015, the new lawsuit presents what’s called an “as-applied challenge.” Plaintiffs in this suit, led by the N.C. Association of Educators teachers union, argue that the way that state has operated the program renders Opportunity Scholarships unconstitutional.

Despite the difference in the type of constitutional challenge employed this time, basic arguments against the scholarships haven’t changed much in five years. What has changed substantially is the makeup of the state Supreme Court.

Of the four members who voted in 2015 to uphold Opportunity Scholarships, only one — Justice Paul Newby — remains on the bench. Meanwhile, all three dissenters remain on the high court. One of them, Cheri Beasley, has moved from an associate justice’s seat to the chief justice’s role.

Moreover, the original vote upholding Opportunity Scholarships broke down along party lines, with four Republican justices overruling three Democrats. Now Democratic justices outnumber Republicans, 6-to-1.

The numbers bode ill for the program’s future.

If critics succeed in killing off Opportunity Scholarships, many of the thousands of students who use them today will have no choice but to return to traditional district schools where they struggled in the past.

This brings us back to Nariah.

Born prematurely, she faced early hearing challenges. ”The doctor said it was as if she had earmuffs on her ears and was submerged under water,” her grandmother, Janet Nunn, told me during an interview for the John Locke Foundation’s “HeadLocke” podcast.

That developmental issue caused Nariah to fall behind other students her age. During the first grade, Janet Nunn saw serious problems. “She was sitting in the back,” Nunn said. “Her head would be down. She wasn’t raising her hand. She was very quiet.”

Nunn wanted Nariah to repeat the first grade. The public school system had other ideas. “I knew she wasn’t ready, and I didn’t want her to fall any further behind,” Nunn said. “Well, the school then became concerned about it being a behavior issue because all of her friends from the first grade would move to the second grade.”

Nariah’s grandmother knew she needed to move to a different school. The Opportunity Scholarship made the move possible. Nariah repeated the first grade in her new private school. She caught up on fundamental education building blocks.

Now? “Nariah is a rising sixth-grader,” Nunn says with pride. “She’s a B-average student. She is confident in herself. She believes in herself. … It’s amazing — the transformation. Seeing that transformation, not only in her education and where she’s at, but in her character, in herself. … Without the [Opportunity Scholarship], I wouldn’t have been able to provide that for her.”

The tears start to flow.

Seeing the impact Opportunity Scholarships have in her own home, Nunn responds emotionally to the lawsuit designed to kill the program.

“It’s ridiculous,” she says. “We live in a country that we say is free. We’re supposed to be in the pursuit of the happiness and the freedom. That pursuit is with education as well.”

“I don’t see what’s unconstitutional,” Nunn adds. “Because I’m low-income? Is that what makes it unconstitutional? I want to give my child an opportunity. That’s exactly what the scholarship is. It’s an opportunity for advancement in your life. She has a right to that.”

More tears.

The Institute for Justice has filed paperwork to allow Nunn and two other families to intervene in the lawsuit. This step would enable them to share with the court the real-world positive impact of Opportunity Scholarships.

Nunn would tell Nariah’s story. “Her going from a child that didn’t want to go to school, now she’s eager to go to school,” Nunn says. “She reads. She wasn’t reading before. It’s so much better than what it was.”

“She’s not sitting in the back of a classroom,” Nunn adds, tears welling up again. “She’s not holding her head down. She’s not saying that she’s not as smart as her classmates. … She’s raising her hand. She’s asking questions. She’s moving forward. She wants to be in front, to be that leader.”

“Without this program, I don’t know where she would be.”

Nunn echoes the sentiments of thousands of other families who benefit today from Opportunity Scholarships. One hopes she will have the chance to share her message in a courtroom, not just the court of public opinion.

Mitch Kokai is senior political analyst for the John Locke Foundation.