Overview
- The Supreme Court, which issued its decision Tuesday, June 30, 2026, upheld Idaho’s and West Virginia’s laws in a 6-3 opinion written by Justice Brett Kavanaugh that said Title IX and the Constitution allow eligibility rules based on biological sex.
- The ruling validates comparable bans in more than two dozen states and does not require states to separate teams but permits them to enforce sex-based eligibility rules for girls’ and women’s school and college sports.
- Three liberal justices sharply dissented on the Equal Protection analysis, arguing the Court cut off factual fact-finding about individual athletes who say they received puberty blockers or hormone treatment and therefore lack a male physiological advantage.
- The decision strengthens the Trump administration’s policy stance that would withhold federal support from programs that let transgender girls compete on girls’ teams and is likely to prompt renewed enforcement actions and new legal challenges in jurisdictions that continue to allow transgender participation.
- Beyond the immediate cases, the ruling leaves open factual and legal questions—including how to assess physiological advantage in particular athletes—and signals more litigation and policy fights ahead over who may play on girls’ and women’s teams.