The most critical exchanges in the United States v. Skrmetti argument at the Supreme Court involved two concessions by U.S. Solicitor General Elizabeth Prelogar in response to questions by Justices Barrett, Thomas, and Alito. Prelogar’s central argument has been that Tennessee’s law regulating use of puberty blockers and cross-sex hormones to transition children discriminates based on sex because those drugs can be used for other purposes — e.g., to treat precocious puberty and endocrine disorders — in children who are not transitioning. So, she insists, the state lets a doctor prescribe estrogen to an adolescent female to treat an endocrine disorder but not to an adolescent male who seeks to undergo transition — and thus the statute facially discriminates.

But this facial discrimination argument fell apart in the face of questioning by Justices Barrett and Thomas. Justice Barrett posed a hypothetical of a new drug that is used only for gender-transition purposes and that the state prohibits for use by minors. (This hypothetical tracks a similar one in a brief I filed on behalf of Concerned Women for America and Samaritan’s Purse, excerpted below.) Perhaps surprisingly, Prelogar quickly conceded that this hypothetical law would not facially discriminate based on sex. Thus, Prelogar’s facial discrimination argument depends on the notion that transitioning interventions are the same as other medical treatments that happen to use the same underlying medications.

Yet in response to Justice Thomas, Prelogar conceded that males and females have physiological differences and that those differences mean that their bodies react differently to sex hormones (testosterone and estrogen). Males and females are thus not similarly situated when it comes to administration of these hormones — so giving adolescent girls estrogen for an endocrine disorder is not the same as letting male youths take estrogen as part of transition. And without differential treatment, there is no facial discrimination, and no heightened scrutiny.