Certain gender-affirming surgeries that could be provided to people assigned male at birth and people assigned female at birth are provided to only one group under the policy. Those surgeries include vaginoplasty (for congenital absence of a vagina), breast reconstruction (post-mastectomy), and breast reduction (for gynecomastia).... Those assigned female at birth can receive vaginoplasty and breast reconstruction for gender-affirming purposes, but those assigned male at birth cannot. And those assigned male at birth can receive a mastectomy for gender-affirming purposes, but those assigned female at birth cannot. In other words, when the purpose of the surgery is to align a patient’s gender presentation with their sex assigned at birth, the surgery is covered. When the purpose is to align a patient’s gender presentation with a gender identity that does not match their sex assigned at birth, the surgery is not covered....

This is textbook sex discrimination, for two reasons. For one, we can determine whether some patients will be eliminated from candidacy for these surgeries solely from knowing their sex assigned at birth. And two, conditioning access to these surgeries based on a patient’s sex assigned at birth stems from gender stereotypes about how men or women should present....

Try figuring out whether the State Health Plan or Medicaid Program will cover a certain patient’s vaginoplasty. By virtue of the fact that they are seeking a vaginoplasty, we know that they were born without a vagina. But we do not know what sex they were assigned at birth. Without that information, we cannot say whether the Plan or Program will cover the surgery....

The Supreme Court used this type of thought experiment in Bostock v. Clayton County. There, it imagined a job applicant asked to disclose the applicant’s sexual orientation.... “There is no way for an applicant to decide whether to check the homosexual or transgender box without considering sex,” it wrote.... “To see why, imagine an applicant doesn’t know what the words homosexual or transgender mean. Then try writing out instructions for who should check the box without using the words man, woman, or sex (or some synonym). It can’t be done.”... The same is true here. A third-party administrator cannot make the coverage decision without knowing whether the vaginoplasty is to treat gender dysphoria—in other words, whether the patient was assigned male at birth.

[Footnotes omitted]