The Supreme Court is weighing whether it needs to rule on a legal definition of sex under federal law as it evaluates whether two state laws restricting women’s sports to biological females are constitutional. Such a ruling could have a profound effect on laws governing transgender issues across the country.
The Supreme Court on Tuesday heard arguments in a pair of cases, Little v. Hecox and West Virginia v. B.P.J., which focus on state laws that restrict women’s sports to biological females. The Hecox case deals with whether an Idaho law violates the equal protection clause and was brought by a college-aged biologically male athlete. The B.P.J. case, meanwhile, is challenging a West Virginia law under both the Equal Protection Clause and Title IX, and was brought by a biologically male middle school student who is now in high school.
The issue of whether the justices should define sex, especially under Title IX, emerged as one of the key questions during back-to-back oral arguments. Justices asked both sides throughout the arguments how sex should be legally defined. Justice Clarence Thomas, for example, asked West Virginia Solicitor General Michael Williams how the state would define sex under Title IX, which prohibits sex-based discrimination at schools, and Williams said he would define it based on biological sex. Justice Department lawyer Hashim Mooppan also referred to biology as the basis of legal standards regarding sex.
As he argued for the West Virginia law to be struck down under Title IX, Joshua Block, lawyer for the student identified in court papers as B.P.J., faced a series of questions from the justices about his side’s definition of sex. Chief Justice John Roberts asked Block if he was arguing that the definition of girls should include “transgender girls,” biological males who identify as girls. Justice Brett Kavanaugh asked if the definition of sex in Title IX allows for different states to have different laws about the inclusion of biological males who identify as women in women’s sports.
Block told the justices it was not necessary for the high court to rule on the definition of sex and ultimately asked them not to give a firm definition for sex under Title IX.
“I don’t think the purpose of Title IX is to have an accurate definition of sex, I think the purpose is to make sure sex isn’t being used to deny opportunities,” Block said.
“I wouldn’t look to whether or not it’s accurate to classify B.P.J. as male or female, I think the question is, is [B.P.J.] being denied an opportunity because of that classification,” Block added.
Both Roberts and Justice Samuel Alito questioned how the justices could find that a state law discriminates on the basis of sex if they don’t have an actual definition of sex.
While Block continued to argue the high court should not define sex, he also argued that sex and gender identity are the same thing.
Roberts, Thomas, and Alito, along with Kavanaugh and Justice Amy Coney Barrett, appeared more skeptical of the arguments made by the lawyers for the transgender athletes in both cases. Those same five justices made up most of the majority in the United States v. Skrmetti case from June 2025, which allowed a state ban on transgender procedures for minors to remain in place.
Justice Neil Gorsuch, who wrote the 2020 Bostock v. Clayton County decision, which ruled that firing someone based on gender identity violates Title VII, appeared skeptical of both sides’ arguments in both cases, offering sharp questions throughout the hearing.
Justices Sonia Sotomayor, Ketanji Brown Jackson, and Elena Kagan appeared more skeptical of both Idaho and West Virginia’s arguments in support of their transgender sports bans. Kagan questioned Block on how the high court can issue a ruling that would not wipe out the laws of the 23 states that currently permit biological males to compete in women’s sports.
A PAIR OF SUPREME COURT CASES PUT THE FUTURE OF TITLE IX IN THE BALANCE
The Supreme Court is expected to release opinions in both cases by the end of June. The two cases are some of the most highly anticipated decisions still to come from the high court this term.
The pair of cases regarding women’s sports laws is among several other high-profile cases the justices have heard or will hear this term. Other notable cases include challenges to President Donald Trump’s sweeping tariffs, birthright citizenship, late-arriving mail ballots, and gun laws.