AMNA NAWAZ: One of the most hotly debated political issues in recent years made its way to the U.S.

Supreme Court today.

At issue, can transgender athletes compete alongside women and girls?

The conservative majority seemed skeptical of striking down sports bands already in place in over half of all states.

But, for over three hours, the justices examined the constitutional arguments over science and whether trans athletes are competing on an equal playing field.

Liz Landers has a closer look at the legal and political fight before the nation's highest court.

LIZ LANDERS: Becky Pepper-Jackson says she's not much different than other teenagers.

She plays multiple instruments and likes to spend time at home with her pets.

But the West Virginia high school student has spent years at the center of a political firestorm, because, as a transgender girl, she's looking to stay on her school's track team.

That's despite a state law that bars transgender girls from playing on girls sports teams at public schools and colleges.

BECKY PEPPER-JACKSON, Transgender High School Athlete: Letting these awful laws and bills just stand is not something that should happen.

LIZ LANDERS: Her case is one of two before the nation's highest court, as justices weigh if statewide bands against transgender students from participating in women's sports are constitutional.

Some female athletes have stepped in to support bans, saying it's an issue of fairness.

LAINEY ARMISTEAD, Former Soccer Captain, West Virginia State University: I love soccer and it opened up opportunities for me that I never would have had without it.

LIZ LANDERS: Lainey Armistead played soccer at West Virginia State University.

She intervened in the case to defend the ban in 2021 while she was a student.

LAINEY ARMISTEAD: The West Virginia law doesn't exclude anyone from playing sports.

It just promotes a safe and fair category for women.

LIZ LANDERS: In the years since, Armistead has dedicated her time to fight for the bans in court and at a United Nations event.

LAINEY ARMISTEAD: This stance is about preserving biological reality and saying women deserve a fair place to play, a safe place to play and not be put at risk.

LIZ LANDERS: The second case before the court today centers around Lindsay Hecox, a young woman who previously competed in track at Boise State University in Idaho.

The "News Hour" spoke to her in 2021 at the start of her legal battle.

LINDSAY HECOX, Transgender Athlete: Gender dysphoria just sucks.

You don't get to be the person you were meant to be just because of some random luck when you were born.

LIZ LANDERS: Both Pepper-Jackson and Hecox live in one of the 27 states that have a law or regulation that prevents transgender girls and women from participating in sports based on their gender identity.

And both have fought yearslong legal battles to maintain the right to compete in track and field, while Republican leaders fought them in court.

President Trump also signed an executive order last year threatening to withhold federal funding from programs that allow transgender women and girls to compete in women's sports.

JOSHUA BLOCK, ACLU: All that we're asking for is basic fairness and letting Becky have the same childhood experience as anyone else.

My name is Josh Block.

LIZ LANDERS: Joshua has represented Pepper-Jackson for several years for the ACLU.

He says she doesn't have an unfair physiological advantage against other girls her age because she's been taking puberty-blocking medication since the third grade.

JOSHUA BLOCK: So, that's one of the fundamental problems with laws like this, these sweeping bans, is that they refuse to look at the individual, that the whole point of our civil rights laws and the Constitution's Equal Protection Clause is that people should be recognized as individuals and not just part of amorphous groups.

LIZ LANDERS: There's been little scientific research on if transgender women actually have an advantage against their competitors.

DR.

BRADLEY ANAWALT, University of Washington: The caveat to all of this is that we don't have a lot of high-quality data.

LIZ LANDERS: Dr.

Bradley Anawalt is an endocrinologist and professor at the University of Washington who has advised athletic associations on hormone use in sports.

He says that transgender girls who were prescribed puberty-blockers like Pepper-Jackson have few biological differences from their teammates.

DR.

BRADLEY ANAWALT: The ability to do something, a feet of strength over a short period of time, speed or endurance events, all of those advantages that might occur with testosterone don't occur with these people that are started on gender-affirming hormone therapy and specifically puberty blockers shortly after the development of puberty.

LIZ LANDERS: While it may be the first time the court has weighed in on transgender athletes, it's one of a series of recent cases focused on transgender students.

Just last year, a majority of justices upheld Tennessee's ban on gender-affirming care for minors.

In the court's majority opinion, Chief Justice John Roberts wrote the court will leave the issue to -- quote -- "the people, their elected representatives and the democratic process."

That ruling could signal how the court might decide this case.

KRISTEN WAGGONER, Alliance Defending Freedom: It will be women and girls that suffer the most when biological distinctions are not recognized in the law when those distinctions matter.

LIZ LANDERS: Kristen Waggoner is the president of the Alliance Defending Freedom, a conservative legal group that's worked alongside Idaho and West Virginia in both cases.

KRISTEN WAGGONER: There are hundreds of girls and women who have been displaced, and let's be clear about what that means.

It doesn't just mean that they don't get podiums.

It actually means that they do lose scholarships, which then means that they don't have access to higher education in the same way that they should.

LIZ LANDERS: In oral arguments, Justice Brett Kavanaugh expressed those same concerns about displacing women in sports and how different courts have ruled on the issue.

BRETT KAVANAUGH, U.S.

Supreme Court Associate Justice: And so one way to resolve it, as you say, is the facts, try to figure out, is there really a competitive advantage?

I think we're going to get a lot of scientific uncertainty about that, a lot of debate about that, a lot of different district courts.

LIZ LANDERS: Block and the ACLU acknowledge Pepper-Jackson may face an uphill battle.

JOSHUA BLOCK: Athletics is so unique.

There really is no justification for West Virginia and Idaho to try to use this really unique context to establish a sweeping principle that the government can freely discriminate against transgender people.

LIZ LANDERS: It's a point that Justice Ketanji Brown Jackson also made in arguments today.

KETANJI BROWN JACKSON, U.S.

Supreme Court Associate Justice: I guess I'm struggling to understand how you can say that this law doesn't classify on the basis of transgender status.

The law expressly aims to ensure that transgender women can't play on women's sports teams.

So why is that not a classification on the basis of transgender status?

LIZ LANDERS: "News Hour" Supreme Court analyst and SCOTUSblog co-founder Amy Howe says it's likely the court's conservative majority will side with the states based on today's arguments.

AMY HOWE: This is a conservative court, and conservative groups and conservative plaintiffs see the opportunity to bring these kinds of cases to the court because they believe they will find a receptive audience.

LIZ LANDERS: Until that ruling, the political firestorm over fairness in women's sports will continue on and off the field.

For the "PBS News Hour," I'm Liz Landers.