The Supreme Court on Tuesday ruled that states can block biological transgender males from competing in girls' sports. In a 6-3 ruling, the court gave an iron-clad answer to the question.
Writing for the majority in West Virginia v. B.P.J. (consolidated with Little v. Hecox), Justice Brett Kavanaugh held that neither Title IX nor the Equal Protection Clause requires schools to carve out an exception for transgender athletes who've undergone hormone therapy or never experienced male puberty. States can draw the line at biological sex, full stop - no judge-administered athlete-by-athlete fairness hearings required. The ruling reverses both the Fourth Circuit (which sided with West Virginia's B.P.J.) and the Ninth Circuit (which sided with Idaho's Lindsay Hecox), and lands squarely in the wake of last year's Skrmetti decision, extending its "this is a sex classification, not a transgender classification" framework from medical care straight into the locker room.
Roughly half the states - approximately 27 - have enacted laws in recent years restricting participation in girls' and women's school sports to those whose biological sex, as determined at birth, matches the team category. These measures, often titled "Fairness in Women's Sports" acts or similar, reflect concerns over competitive fairness, safety, and the preservation of opportunities for biological females amid rising participation by transgender athletes.
The two cases before the Court arise from Idaho and West Virginia.
Idaho's law (enacted 2020) categorically bars transgender girls and women from girls' and women's teams in public elementary, secondary, and postsecondary schools. It defines eligibility based on biological sex and requires sex verification (often involving invasive procedures) for athletes on girls' teams but not boys' teams.
West Virginia's law (enacted 2021) similarly requires that participation on teams designated for girls or women be based on biological sex.
Lindsay Hecox, a biological male, challenged Idaho's law after seeking to compete on Boise State University's women's track and cross-country teams - and later participated in club sports. Hecox's lawsuit alleged violations of the Equal Protection Clause of the 14th Amendment, claiming the law discriminates on the basis of sex and transgender status and imposes unequal verification burdens.
B.P.J., another biological male who has identified as a girl since third grade and has taken puberty blockers and estrogen, challenged West Virginia's ban after competing on their high school's girls' track and cross-country teams. The suit claims violations of both the Equal Protection Clause and Title IX (the federal law prohibiting sex discrimination in federally funded education programs).
Lower federal courts blocked enforcement of both laws. The 9th Circuit found Idaho's measure likely violated equal protection by intending to exclude transgender girls/women and by imposing sex-based verification only on girls' teams. The 4th Circuit held West Virginia's law likely violated Title IX by discriminating against B.P.J. on the basis of sex.
At oral arguments on January 13 of this year, the states and supporting parties (including the Trump administration) argued that the laws classify on the basis of biological sex - a classification long accepted in sports to ensure fairness and safety given average physiological differences in strength, speed, muscle mass, bone density, and cardiovascular capacity that emerge after male puberty. They contended that sex-separated teams are permissible and even required under Title IX regulations, that states need not create perfect individual accommodations, and that allowing transgender girls/women (even those on hormone therapy) into female categories undermines the very purpose of sex-segregated sports. They emphasized that transgender boys can generally compete on boys' teams, so the laws do not single out transgender status per se.
Challengers countered that the bans discriminate on the basis of transgender status and sex, that many transgender girls/women (especially those who never experienced full male puberty or who have undergone hormone suppression) lack meaningful competitive advantages, and that categorical exclusion stigmatizes transgender students, deprives them of athletic opportunities, and violates both constitutional equal protection and Title IX's promise of equal access. They urged individualized assessments rather than blanket rules.
Justices' questioning suggested a likely majority inclined to uphold the state laws, with conservative members emphasizing biological differences, state authority over education and athletics, and deference to longstanding sex-based categories in sports.