Yesterday the United States Supreme Court ruled that homosexual and transgender people are protected from discrimination under Title VII of the 1964 Civil Rights Act. Many did not expect this result given the Court’s conservative majority. The crux of the issue in Bostock and the companion cases was whether Title VII’s prohibition against discrimination on the basis of sex covers sexual orientation and gender identity. (Although there has been much discussion in the popular press about the use and meaning of the word “sex” in the statute, the Court gave that word its ordinary meaning circa 1964: status as either male or female as determined by reproductive biology.) What surprises me the most about yesterday’s decisions is that the Court’s reasoning is not the reasoning the plaintiffs had urged it to adopt. In fact, the rulings are so laughably simple that I have to wonder if anyone saw this coming.

The employers in yesterday’s cases admitted that they fired the plaintiffs because of sexual orientation or transgender status. They simply argued that Title VII does not forbid their actions.

Plaintiffs were trying to extend reasoning first adopted in Price Waterhouse v. Hopkins. Ann Hopkins was an associate at Price Waterhouse who was denied partnership despite having an exemplary work history and a substantial book of business. When she asked male partners the reasons for their decision, they explained that it had nothing to do with her work. She was too aggressive, didn’t act feminine enough, and didn’t dress or style her hair the way they believed a woman should. She sued. Price Waterhouse contended that it could not be guilty of sex discrimination because it had made partners of other women who conformed to their expectations.

Hopkins won. She successfully argued that an employer discriminates on the basis of sex if it conditions employment on conformance to standards of appearance or conduct that are based on gender stereotypes. Thus, it didn’t matter that Price Waterhouse elevated other women to partnership. What mattered was that a woman would only be considered for partnership if she was the “right kind” of woman, and the employer’s notion of what constituted the “right kind” of woman was based on sexist stereotypes.

The plaintiffs in yesterday’s cases were trying to extend the reasoning of Hopkins. They claimed they were fired because they weren’t the “right kind” of men and women as defined by stereotypical ideas about gender norms, and thus could seek redress under Title VII even though the law wasn’t specifically written to cover homosexuality and transgender.

The Court didn’t bite. It declined to address gender stereotypes or the changing perceptions of gay and transgender people. In fact, in a certain sense it didn’t address the rights of gay and transgender people at all. Instead, the Court reasoned as follows: Employees A and B are both attracted to women. Employee A is a man; he can stay. Employee B is a woman; she’s fired. The only distinction between A and B is their sex. It’s okay for A to be attracted to women because he’s a man. It isn’t okay for B because she’s a woman. That’s discrimination on the basis of sex. Boom, we’re done.

The same reasoning applies to transgender employees. Behavior that is tolerated in one employee because she was born female is not tolerated in another because she was born male. That distinction—sex—is the basis for distinguishing between them. That’s sex discrimination. Boom, we’re done.

There’s a sense in which the simplicity of this argument is brilliant. It is simply beyond argument that the defendant employers tolerated behavior in other employees that they did not tolerate in the plaintiffs, and the reason for the disparate treatment is the sex of the employees. The logic of the decisions is unassailable.

But it’s also narrow. The Court made no broad declarations about the rights of gay and transgender people. It did not find that they have been subject to a history of invidious discrimination. Thus, it did not define them as a protected class such that constitutional claims under the Due Process or Equal Protection clauses of the Fourteenth Amendment will receive special attention. In fact, it did not decide any constitutional claims at all. Yesterday’s cases were brought under a federal statute. Congress can amend that statute if it pleases, although it probably won’t. The Court did not find that Congress intended Title VII to cover gay and transgender people. It did not find that the needs of gay or transgender employees must be accommodated in any way that does not involve disparate treatment on the basis of sex. For this reason, yesterday’s rulings are a significant victory for gay and transgender people. But it is an incomplete victory, and it does not represent full equality under the law.