The Supreme Court will dive headfirst into the politically fraught issue of transgender rights on Wednesday when it hears a challenge to Tennessee’s ban on gender-affirming care for minors in the highest-profile case of the fall.

Attorneys for the Biden administration and transgender youth in Tennessee will press the justices to declare the 2023 law an unconstitutional form of sex discrimination, while the state’s lawyer plans to argue that lawmakers were justified in restricting medical care for residents under the age of 18.

“I hope that we win this case. And I hope that that means they can get access to the care they need,” L. Williams, one of the minors challenging the law, told CNN, referring to other trans kids facing health care bans like Tennessee’s.

The conservative-majority court will examine the law at a critical time for transgender Americans. Since 2020, Republican-led states around the country have passed a wave of laws regulating the lives of trans Americans, with a particular focus on minors. And though the community makes up a small fraction of the American public, it featured prominently during the 2024 election and its aftermath, with President-elect Donald Trump amplifying his pledge to further curtail civil rights for trans people during the closing days of the campaign.

Depending on how the court rules, similar prohibitions on gender-affirming care – and, potentially, other laws targeting transgender people – would be at risk of falling altogether or receiving a powerful endorsement from the high court.

Here’s what to know about the case:

Justices may decide how much protection transgender people have

The case, known as US v. Skrmetti, represents only the second time in recent years that the court has been tasked with deciding the extent to which federal law protects transgender people from discrimination.

The last time the court tackled that question was in a case from 2020 called Bostock v. Clayton County. In that matter, the majority, led by conservative Justice Neil Gorsuch, ruled that federal law prohibiting sex-based discrimination in the workplace applies to gay and transgender workers since such action “necessarily” happens because of that person’s sex.

Since then, lower courts around the country have grappled with how to apply the legal rationale that emerged in Bostock in other cases dealing with transgender issues.

This case will have an even greater impact on other laws concerning transgender people, legal experts say. That’s partly because the court may decide whether trans Americans as a group are entitled to receive protection from discrimination.

“This is going to be their first opportunity to address the rights of the transgender community under the equal protection clause, especially in view of the vast proliferation of state legislation targeting transgender individuals, and, in particular, transgender youth,” said Katie Eyer, a professor at Rutgers Law School who joined a friend-of-the-court brief supporting the law’s challengers.

“It’s an incredibly important case,” she added. “It will set the tone for and set the law for what type of scrutiny these laws will be subjected to across the board.”

What the Tennessee law does

The Tennessee law at the center of Wednesday’s arguments was signed by Republican Gov. Bill Lee in 2023. Known as SB 1, the measure bans hormone therapy and puberty blockers for minors in the state and imposes civil penalties for doctors who violate the prohibitions. It also bans gender-affirming surgeries, though that provision is not at issue in the case.

Specifically, the law prohibits providers in the state from administering such care if the purpose is to enable “a minor to identify with, or live as, a purported identity inconsistent with the minor’s sex,” or treat “purported discomfort or distress from a discordance between the minor’s sex and asserted identity.”

The Republican lawmakers who crafted the law wrote in their legislative findings that “minors lack the maturity to fully understand and appreciate the life-altering consequences of such procedures” and that the state “has a legitimate, substantial, and compelling interest in encouraging minors to appreciate their sex, particularly as they undergo puberty.”

Crucially, the law makes an exception for doctors to provide the same otherwise prohibited care to cisgender minors seeking treatment for a congenital defect or early puberty, among other things.

A slew of other GOP-led states have passed similar health care bans in recent years. Today, more than 110,000 teenagers live in states where restrictions on puberty blockers and hormone therapy exist, according to the Williams Institute at UCLA School of Law.

‘Life-changing’ care

L. Williams told CNN this week that receiving gender-affirming care has been “life-changing,” giving her more confidence as she navigates adolescence.

“It’s been very helpful, very helpful – life-changing,” she said. “For some people, it’s even been life-saving.”

The state’s ban has forced her to travel out of state to continue receiving care for her gender dysphoria, the medical term for an uncomfortable conflict between a person’s assigned gender and the gender with which the person identifies. The travel is a stressful reality that has caused the high school junior to frequently miss school.

“It’s also very terrifying because I didn’t know what I was going to do without the care because it certainly left me in a much better place mentally than I was a few years ago,” she said of the state’s decision to restrict the care. “I was just terrified of what would happen.”

Williams will be in the courtroom on Wednesday to witness the historic arguments unfold – a unique position that seemed unlikely for the 16-year-old.

“I couldn’t imagine that I would be headed to the Supreme Court,” she said.

How the case got to SCOTUS

SB 1 was initially challenged by three trans minors in Tennessee, their parents and a doctor in the state whose practice included intreating minors for gender dysphoria.

The Biden administration later joined that lawsuit and a federal judge in Tennessee sided with the challengers in June 2023.

Judge Eli Richardson, a Trump appointee, said in a ruling temporarily blocking the law that the measure violated the equal protection clause of the 14th Amendment. The judge reviewed the law under a standard of review known as heightened scrutiny and decided that since it “likely is not substantially related to the state’s asserted interest” it is unconstitutional.

Notably, Richardson ruled that SB1 “discriminates based on transgender status and that transgender individuals constitute a quasi-suspect class” that qualify for additional protections under the law.

The state appealed to the Cincinnati-based 6th US Circuit Court of Appeals, which decided that the law should be subject to the lowest standard of review, called rational basis. A divided three-judge panel said that transgender people are not part of a “quasi-suspect class” and that the legal reasoning in Bostock does not apply outside the context of workplace discrimination.

The appeals court ruling was authored by Chief Judge Jeffrey Sutton, a George W. Bush appointee, and joined by Judge Amul Thapar, a Trump appointee. Judge Helene White, a Bush appointee, dissented.

The challengers filed separate appeals to the Supreme Court, which decided in June to review only the administration’s case.

What each side will argue

The case will turn on what level of scrutiny the justices decide is appropriate for examining SB 1. But that ruling, expected before July, will extend far beyond Tennessee’s borders: It will help guide judges on lower courts who are handling disputes related to anti-trans laws on bathroom access, school sports and pronouns, among other things.

Lawyers for the Biden administration have asked the justices to consider whether the law passes constitutional muster under heightened scrutiny, which requires states to show they have an important government interest in banning treatment and that the law achieves that goal in a way that’s “substantially related” to its interest.

Should the Supreme Court examine the law under that standard, Solicitor General Elizabeth Prelogar wrote in court papers, “it should hold that SB1 cannot survive heightened scrutiny” based on a long line of cases in which the court “has consistently held that all sex-based classifications are subject to heightened scrutiny because such classifications too often reflect stereotypes about how men and women should look or act.”

The administration told the court that “transgender individuals satisfy all of the hallmarks of a quasi-suspect class,” a position that, if adopted by the high court, would also give the advocates for the community a powerful tool when challenging laws like SB 1 in court.

Prelogar also told the justices that they could, alternatively, send the case back to the appeals court to consider whether SB 1 is constitutional under the higher standard of review it prefers.

For its part, Tennessee has told the court that the law “includes no sex classification” and that it instead draws an age- and use-based distinction that is permissible under the equal protection clause. In other words, the state says, the law bars the treatment for both boys and girls who want to transition.

Attorneys for the state urged the justices to not “get back in the fraught business of creating suspect classes” and warned that doing so in this case would, in their view, wrongly give transgender women the same legal protections as cisgender women.

“If the government’s theory holds, men who identify as women could claim constitutionally based access to women’s bathrooms, women’s locker rooms, and women’s sports,” they wrote. “Accepting that theory would perversely erode women’s rights and jeopardize landmark statutes protecting women’s equal access to schools, winners’ podiums, and beyond.”

Roberts, Gorsuch among the justices to watch

The Supreme Court last touched on transgender rights in a substantive way four years ago in a surprising decision that held federal law bars discrimination against gay and transgender employees in the workplace.

The reason: Such discrimination is necessarily based on sex.

Part of the reason why the Bostock decision was unexpected was because of the author: Gorsuch. The Trump nominee was joined in the majority by Chief Justice John Roberts as well as the court’s liberal wing. The court’s other conservatives at the time – Justices Clarence Thomas, Samuel Alito and Brett Kavanaugh – dissented.

“It is impossible to discriminate against a person for being homosexual or transgender without discriminating against that individual based on sex,” the 6-3 majority said.

Because the Biden administration is relying in part on Bostock, both Roberts and Gorsuch will be key votes to watch during the arguments.

The Bostock majority stressed that the decision dealt only with the workplace. But trans rights advocates say it’s difficult to see how the logic the court used in Bostock – that discrimination against transgender workers is necessarily discrimination based on sex – wouldn’t apply in other contexts.

Another justice to watch is Amy Coney Barrett – a Trump nominee who sometimes breaks with conservative ideology.

Barrett wasn’t sitting on the court when Bostock was decided. She was picked to fill the seat of Justice Ruth Bader Ginsburg, a liberal icon whose death a few months after Bostock was decided helped move the court further to the right.

Justices will hear from trans lawyer

Chase Strangio, one of three attorneys who will be parrying questions from the justices over the course of the arguments, will make history as the first known transgender person to argue before the Supreme Court.

Strangio, an American Civil Liberties Union lawyer, will be speaking on behalf of the three transgender minors and their families who initially challenged the Tennessee law.

“It is not lost on me that I will be standing there at the lectern at the Supreme Court in part because I was able to have access to the medical care that is the very subject of the case that we’re litigating,” Strangio told CNN.

Prelogar will argue first, representing the Biden administration. Widely respected for her advocacy among both conservatives and liberals, it is possible the trans case will be Prelogar’s last major argument before the high court.

Tennessee will be represented by J. Matthew Rice, a former clerk to Justice Thomas – and one-time professional baseball player – who is making his debut before the justices.

A fight over medicine

Intertwined with the legal arguments over the law is a fight over the thorny issue of modern medicine and which health experts the court should listen more closely to.

Major medical associations – including the American Medical Association, the American Psychiatric Association and the American Academy of Pediatrics – agree gender-affirming care is clinically appropriate for children and adults, and research shows the risk of suicide is high among youth who experience gender dysphoria.

The Biden administration and a host of outside groups have leaned into those points as they’ve asked the court to consider the impact of a ruling in favor of Tennessee.

“Denying access to medical care and treating transgender youth disparately because of their transgender status are correlated with substantially increased risks of suicide and negative mental health outcomes,” the Trevor Project, a nonprofit that works to prevent suicide among LGBTQ youth, told the justices in one friend-of-the-court brief.

On the other hand, Tennessee’s attorneys describe the banned treatments as “risky, unproven gender-transition interventions” that they say can cause irreversible changes to minors.

“While the government is free to favor its transition-first, ask-questions-later approach, the Constitution does not bind Tennessee to that same choice,” they wrote.

Among the groups backing Tennessee’s approach is Do No Harm, Inc., a conservative medical advocacy group whose chairman told CNN that while the organization doesn’t oppose gender-affirming care for adults, it believes such care should not be administered to minors.

“Adults can do as they as they will, and there are perfectly fine people that have transitioned. That’s their business,” said Dr. Stanley Goldfarb. “But we feel that children just are really unable to do this in a way that involves informed consent, primarily, and that many of them are just children that are very troubled.”

Trump looms large over historic case

Trump ran for reelection in part on a message of ending “transgender craziness” and he specifically attacked Vice President Kamala Harris for supporting “they/them,” a reference to pronouns sometimes used by transgender and non-binary individuals. The Skrmetti appeal is likely to still be pending at the Supreme Court when Trump moves into the White House on January 21.

If the incoming Department of Justice announces it is changing positions, that could give the Supreme Court an out – an opportunity to dismiss the appeal. On the other hand, with the case fully briefed and argued there’s a good chance the court would simply proceed as planned.

“It’s not all that unusual,” said Pratik Shah, a veteran Supreme Court attorney who is working with the ACLU on behalf of the trans clients. “It shouldn’t change anything in terms of the court’s ability and process for deciding the case.”

CNN’s Casey Gannon and Chelsea Bailey contributed to this report.