The argument that Tennessee's law discriminates based on sex was laid out multiple times and is fairly simple. If a boy seeks puberty blockers to prevent precocious puberty, he can get them. If a transgender boy seeks them to stop puberty, he cannot get them. In other words, access to the drug depends on the biological sex of the child requesting it. That, the plaintiffs argue, is sex discrimination. The law "prohibits inconsistency with sex," Prelogar argued, in the same way that laws once prohibited people dressing like the opposite sex or women from pursuing certain professions.
Tennessee denies any sex discrimination, arguing instead that it is not banning access to puberty blockers and hormones based on sex, but rather purpose. If a boy seeks puberty blockers to stop precocious puberty, the drugs are allowed. If the same boy requests them to treat gender dysphoria, the drugs are denied. The underlying medical condition is different. "Its application turns entirely on medical purpose, not a patient's sex," Matthew Rice, Tennessee's solicitor general, told the justices Wednesday.
The problem with that analysis, the liberal justices countered, is that the purpose of hormones and puberty blockers is to control sexual development. If a boy and a girl both want to take testosterone for the same purpose—perhaps to deepen the register of their voice—only the boy can do so, Jackson pointed out. As Prelogar put it, under the law "you can't have these medications to live or identify in a manner inconsistent with your sex." Kagan was more blunt. "It's a dodge to say that this is not based on sex, it's based on medical purpose, when the medical purpose is utterly and entirely about sex."…
