Background
West Virginia’s 2021 Save Women’s Sports Act and Idaho’s 2020 Fairness in Women’s Sports Act both prohibit biological males from competing on female school sports teams, defining sex by biology. Both laws were enacted amid national debate over whether biological males who identify as female and who take puberty blockers or cross-sex hormones should be permitted to participate in women’s and girls’ athletics.
B.P.J., a biological male who identifies as female, began taking puberty blockers in elementary school and hormones in sixth grade. After a West Virginia school principal informed B.P.J.’s mother that B.P.J. could not join the girls’ cross-country and track-and-field teams, B.P.J. sued, alleging violations of Title IX and the Equal Protection Clause. The district court granted summary judgment for the State on both claims, but the Fourth Circuit reversed on the Title IX claim and remanded on equal protection. In the Idaho case, respondent Hecox—a biological male who identifies as female and takes hormones—sued after the Fairness in Women’s Sports Act was enacted; both the district court and the Ninth Circuit blocked the Idaho law on equal protection grounds.
The Supreme Court consolidated both cases and granted certiorari to resolve whether, under Title IX and the Fourteenth Amendment’s Equal Protection Clause, schools may limit female sports teams to biological females.
The Court’s Holding
Justice Kavanaugh, writing for a six-Justice majority, held that Title IX permits schools to maintain women’s and girls’ sports teams defined by biological sex and that West Virginia permissibly did so. The Court reasoned that “sex” in the 1972 Title IX statute, the 1974 Javits Amendment, and the 1975 HEW regulations unambiguously meant biological sex at the time of enactment—not gender identity. The implementing regulations expressly authorize separate teams “for members of each sex” in recognition of inherent physical differences between males and females. The Court rejected B.P.J.’s argument that excluding biological males who have taken hormones is unreasonable under the Javits Amendment, finding that biological-sex-based eligibility rules are reasonable given competitive-fairness and safety concerns, a conclusion reinforced by the parallel judgments of 27 states, the NCAA, the USOPC, and the IOC. The Court also declined to extend Bostock v. Clayton County, 590 U.S. 644 (2020), from the Title VII employment context to Title IX sports.
On equal protection, the Court held that the West Virginia and Idaho laws withstand intermediate scrutiny. Sex-based classifications are permissible when substantially related to an important government objective, and the Court found that safety and competitive fairness are important interests to which biological-sex-based eligibility is substantially related. Citing United States v. Skrmetti, 605 U.S. 495 (2026), the Court characterized the laws as classifying on the basis of biological sex rather than gender identity or transgender status, and ruled that neither facial nor as-applied equal protection challenges succeed. The Court further held that courts—not judges conducting case-by-case hormonal assessments—are ill-equipped to resolve the underlying scientific debates; such line-drawing is appropriately left to legislatures and schools.
The Court reversed the Fourth Circuit’s ruling in the West Virginia case and reversed the Ninth Circuit’s affirmance of the preliminary injunction in the Idaho case, remanding both for further proceedings consistent with its opinion. Justices Thomas and Gorsuch filed separate concurrences. Justice Sotomayor, joined by Justices Kagan and Jackson, concurred in the judgment in part and dissented in part, as did Justice Jackson separately.
Key Takeaways
- “Sex” in Title IX and its implementing regulations means biological sex, not gender identity; schools may therefore limit women’s and girls’ sports teams to biological females without violating Title IX.
- State laws excluding all biological males—including those who identify as female and take puberty blockers or hormones—from female sports teams satisfy intermediate scrutiny under the Equal Protection Clause because safety and competitive fairness are important governmental interests and a biological-sex line is substantially related to those interests.
- Under Skrmetti, laws pegged to biological sex rather than transgender status do not constitute discrimination against transgender individuals as a class for equal protection purposes.
- Courts need not—and constitutionally should not—conduct individualized assessments of each transgender athlete’s physical capabilities; the legislature is the appropriate forum for drawing those lines.
- Bostock and Title VII are inapplicable to the Title IX sports context, which the Court characterized as “vastly different” factually and statutorily from employment discrimination.
Why It Matters
This decision resolves a circuit split and settles—at least as a constitutional and statutory floor—the most contested question in scholastic and collegiate sports policy of the past decade. By holding that biological-sex-based eligibility rules are lawful under both Title IX and the Equal Protection Clause, the Court effectively validates the wave of state legislation that 27 states have enacted since 2020 and aligns federal constitutional law with the recent policies of the NCAA, USOPC, and IOC. Schools and athletic governing bodies in states without such statutes now have clear authority to adopt similar policies.
The ruling’s equal protection analysis has broader implications beyond sports: by reaffirming that sex-based classifications need only satisfy intermediate scrutiny, and by declining to extend heightened protection to transgender individuals as a distinct class, the Court signals how it will approach future legislation distinguishing on the basis of biological sex. The majority’s explicit reservation of the question whether schools may permit—as distinct from require—biological males to compete on female teams leaves open ongoing litigation in lower courts and preserves some policy latitude for states and institutions that choose more inclusive approaches.