Bostock v. Clayton County

Majority reasoning

The majority reasoned that Title VII's "because of sex" language incorporates but-for causation, meaning an employer is liable if sex was one cause of an adverse action even if not the only one. Because firing someone for being gay or transgender requires the employer to treat that individual differently than it would treat someone of a different sex engaged in the same conduct or attraction, sex is necessarily a but-for cause. The Court supported this with hypotheticals: an employer who fires a man attracted to men but not a woman attracted to men is treating the man worse for a trait tolerated in a woman, so sex plays a role. The majority found support in Phillips, Manhart, and Oncale, which established that labels, additional motives, and group-level evenhandedness don't excuse individual sex-based treatment. Responding to the dissents' argument that "sexual orientation discrimination" and "sex discrimination" are conceptually distinct categories, the majority acknowledged the concepts differ but held that discrimination on the first ground cannot occur without discrimination on the second, and that unexpected applications of a broad statute do not create ambiguity justifying departure from its plain terms.

Dissent reasoning

Justice Alito, joined by Justice Thomas, argued that the Court's decision is legislation disguised as interpretation, since in 1964 "sex" meant only biological male or female status and no one understood the statute to cover sexual orientation or gender identity. He argued discrimination on these grounds does not necessarily involve treating individuals differently based on sex, since an employer could implement a policy against hiring gay or transgender people without ever knowing an applicant's biological sex, and extensive historical, statutory, and social evidence shows Americans understood sex discrimination and sexual orientation discrimination as distinct categories. Alito warned the ruling would have sweeping unintended consequences for bathrooms, women's sports, religious employers, healthcare, and speech, and criticized the majority for ignoring 50 years of uniform lower-court precedent and legislative history showing Congress never intended this result. Justice Kavanaugh, dissenting separately, argued that courts must follow the ordinary public meaning of statutory phrases rather than a literal, word-by-word reconstruction, and that "discrimination because of sex" was and is ordinarily understood as a distinct concept from "discrimination because of sexual orientation," as shown by decades of Congress, presidents, and courts treating them as separate categories requiring separate legislation. He contended the proper path for change was through Congress, which has repeatedly considered and nearly passed bills to add sexual orientation protections, and that judicial imposition of this result undermines the separation of powers and democratic accountability, even while praising the underlying goal of protecting gay and lesbian Americans from discrimination.