The Supreme Court voted 5-to-3 today to grant a stay of a lower court ruling that would have allowed a transgender high school student in Virginia to use the bathroom that corresponds with the student’s gender identity. Justice Stephen G. Breyer joined Chief Justice John G. Roberts Jr. and Justices Anthony M. Kennedy, Clarence Thomas and Samuel A. Alito Jr. in voting to grant the stay, noting that he was voting to grant the stay as a “courtesy” in order to preserve the status quo. Justices Ruth Bader Ginsburg, Sonia Sotomayor and Elena Kagan dissented from the stay, without opinion.

Most coverage of the court’s decision, and the lower court opinion in G.G. v. Gloucester County School Board, has focused on the substantive question of whether a school board must allow a transgender student to use those facilities that correspond with the student’s gender identity (as opposed to the student’s biological sex), and whether a failure to do so constitutes unlawful discrimination “on the basis of sex” under Title IX. This is an important question, but it’s not the only important legal issue in the case.

A divided panel of the U.S. Court of Appeals for the 4th Circuit concluded that the school district’s failure to accommodate the student in this case violated Title IX’s prohibition on discrimination “on the basis of sex.” In reaching this conclusion, the court expressly relied upon Auer v. Robbins, which instructs courts to give agency interpretations of their own, ambiguous regulations “controlling weight.” In the process, however, the 4th Circuit majority committed a significant legal error.

The 4th Circuit recognized that the relevant regulations are ambiguous and provide no guidance how schools should accommodate transgender students.

Although the regulation may refer unambiguously to males and females, it is silent as to how a school should determine whether a transgender individual is a male or female for the purpose of access to sex-segregated restrooms. We conclude that the regulation is susceptible to more than one plausible reading because it permits both the Board’s reading—determining maleness or femaleness with reference exclusively to genitalia—and the Department’s interpretation—determining maleness or femaleness with deference to gender identity.

Concluding the regulation was ambiguous, the court proceeded to grant Auer deference to the federal government’s interpretation of the regulation — as stated in a letter sent by the Education Department to the transgender student — and ruled against the school board.

The problem is that the 4th Circuit completely ignored controlling Supreme Court precedent that limits the application of Auer deference. In Gonzales v. Oregon, the Supreme Court held that where a regulation merely parrots the relevant statutory language, agency interpretations are not eligible for Auer deference. The reason for this is that such interpretations are, in actuality, statutory interpretations, and are therefore only eligible for deference under Chevron. To conclude otherwise would enable agency’s to use Auer to circumvent Chevron‘s more demanding requirements.

The agency regulation here merely restated the language contained in Title IX. The regulation, like the statute, prohibits discrimination, including the provision of unequal facilities, “on the basis of sex.” It is about-as-clean an example of a parroting regulation as one can find. For this reason, it is clearly covered by Gonzales v. Oregon, so the 4th Circuit was wrong to provide Auer deference.

The agency interpretation at issue here does not meet the requirements of Chevron deference either, because it was contained in a letter, and is not the result of a notice-and-comment rulemaking or any other action that carriers the force of law. In other words, there was no basis for the 4th Circuit to defer to the agency’s interpretation.

All of the above is not to say that the 4th Circuit reached the wrong result. There is a serious argument that, even in the absence of a controlling agency interpretation, the relevant language of Title IX should be interpreted to require school districts to treat students in accord with their gender identity. There is also an argument that, even if school districts are not required to provide such accommodation, the specific conduct of the school district here constituted actionable discrimination on the basis of sex.

There is an even more serious argument that the language of Title IX is sufficiently ambiguous that the Education Department could adopt a controlling interpretation in a properly promulgated regulation. Under Chevron, I would expect the Education Department to prevail should it ever issue a rule interpreting Title IX to cover transgender individuals in this way. The problem, however, is that the Education Department has never issued such a regulation, and has instead sought to sidestep this process through letters and “guidance” documents.

The bottom line is that whatever one thinks about transgender bathrooms — and the merits of the Supreme Court’s stay — there is plenty not to like about the manner in which the 4th Circuit resolved the issue.