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ACLU Lawyer Stumped When Justice Alito Asks for the Definition of Man and Woman

Dmitri Bolt
Dmitri Bolt  |  January 14, 2026 11:30 AM

Conservative Supreme Court Justice Samuel Alito appeared to corner an American Civil Liberties Union (ACLU) lawyer during oral arguments, when he asked her to define what it means “to be a boy or a girl, or a man or a woman.” The lawyer was unable to provide an answer for the court, and yet her entire argument hinged on the idea that states were violating Title IX, which prohibits discrimination on the basis of sex, a term the ACLU contends includes gender identity.

"Is it not necessary for there to be, for equal protection purposes, if that is challenged under the Equal Protection Clause, an understanding of what it means to be a boy or a girl, or a man or a woman?" Justice Alito asked.

"Yes, your honor," Kathleen Hartnett, the lawyer from the ACLU, replied.

"And what is that definition, for equal protection purposes, what does it mean to be a boy or a girl, or a man or a woman?" Alito asked.

"Sorry, I misunderstood your question," Hartnett said. "I think that the underlying enactment, whatever it was, the policy, the law... We'd have to have an understanding of how the state or the government was understanding that term to figure out whether someone was excluded. We do not have a definition for the Court."

"And we don't take issue with the... We're not disputing the definition here. What we are saying is that the way it applies in practice is to exclude birth sex males categorically from women's teams, and that there is a subset of those birth sex males where it doesn't make sense to do so according to the state's own interest," she added.

"Well, how can a court determine whether there is discrimination on the basis of sex without knowing what sex means, for equal protection purposes?" Alito asked.

"I think here, we just know, we basically know that they have identified, pursuant to their own statute, that Lindsey qualifies as a birth sex male. And she is being excluded categorically from the women's teams as the statute...So we are taking the statutes' definitions as we find them, we don't dispute them, we just..."