Because “gender dysphoria” is a mutable mental state that is the object of psychiatric treatment, it does not resemble the immutable characteristics on the basis of which our precedents have applied heightened scrutiny race, sex, or national origin. Instead, gender dysphoria resembles other characteristics on the basis of which legislatures may classify with a merely rational basis. See, e.g., Heller v. Doe, 509 U. S. 312, 321 (1993) (mental illness); Plyler v. Doe, 457 U. S. 202, 220 (1982) (immigration status). Legislatures have many obvious rational bases to keep men who believe that they are women out of teams and private spaces reserved for women.

Second, as the Court recognizes, this case concerns “biological men” and “boys who identify as girls.” Ante, at 10, 27. Men and boys with gender dysphoria are not women or girls, even if they believe that they are. Sex is an immutable “biological” characteristic, see ante, at 10; it is binary; and “man” and “woman,” “boy” and “girl,” are the terms that correspond to adults and children of each sex. See A. Byrne, Are Women Adult Human Females? 177 Philosophical Studies 3783, 3786-3787 (2020). To use language to obscure reality to show “indifference regarding the truth” is to lie to the public and cease to treat our fellow citizens “as equal[s].” J. Pieper, Abuse of Language-Abuse of Power 17, 21 (1992).