Page:Adams ex rel. Kasper v. School Board of St. Johns County, Florida (2020).pdf/44

 IX or its regulations, we owe it no deference. , 588 U.S. ___, 139 S. Ct. 2400, 2414 (2019) (explaining that deference is not warranted to an agency’s interpretation of its own regulation when that “interpretation does not reflect [the] agency’s authoritative, expertise-based, fair, or considered judgment” (alteration adopted) (quotation marks omitted));, 467 U.S. 837, 842–44, 104 S. Ct. 2778, 2781–82 (1984) (describing deference to an agency’s interpretation of the statute which it administers).

Even if we were to accept the School Board’s argument that sex is “founded in biology” or refers “only to biological distinctions between male and female,”, 140 S. Ct. at 1739, this interpretation does not establish that Mr. Adams is biologically female and belongs in the girls’ restroom. As the District Court found, Mr. Adams—like some other transgender people—has confirmed his male sex not just legally and socially, but medically. 318 F. Supp. 3d at 1300–01. We will not rehash the details of Mr. Adams’s medical transition. But suffice it to say that the School Board’s preferred definition of “biological sex” reduces Mr. Adams “to nothing more than the sum of [his] external genitalia at birth,” to the exclusion of all other characteristics. Appellee’s Suppl. Br. at 11. This understanding of “sex”—or, for that matter, “biological sex”—is as narrow as it is unworkable.