RALEIGH — An order by the U.S. Supreme Court vacating a 4th U.S. Circuit Court of Appeals ruling on a transgender rights issue could affect a North Carolina case related to House Bill 2, a constitutional law expert said.

Greg Wallace, professor of constitutional law at the Campbell University School of Law, said the ruling means U.S. Middle District Judge Thomas Schroeder, the judge handling the lawsuit filed by the ACLU of North Carolina against H.B. 2, will no longer be bound by a previous 4th Circuit’s ruling.

“That means that with respect to Title IX, Judge Schroeder is writing on a blank slate,” Wallace said. “There’s no 4th Circuit decision he’s obligated to follow with respect to transgender students in bathrooms and locker rooms.”

Last year, the 4th Circuit ruled in a Virginia case that Gavin Grimm, a transgender high school student, should be allowed to use the bathroom of his gender identity at his school. The 4th Circuit based its decision on a guidance letter issued by the U.S. Department of Education under President Obama saying the Title IX anti-discrimination law required schools receiving federal funds to allow transgender students to use facilities consistent with their gender identity.

The Trump administration earlier this year rescinded that guidance letter, prompting Monday’s U.S. Supreme Court order to vacate last year’s 4th Circuit ruling. Also last year, Schroeder had granted an injunction favoring three plaintiffs represented by the ACLU of North Carolina based on the 4th Circuit’s previous ruling. That injunction prevented the University of North Carolina system from enforcing the bathroom facilities provision of H.B. 2 for those plaintiffs.

A spokesman for the ACLU said the case will proceed, noting that a hearing on H.B. 2 is scheduled at the 4th Circuit in Richmond, Va., on May 10.

“The decision today doesn’t change the legal protections that transgender people have under Title IX,” Mike Meno, the ACLU spokesman, said Monday. “Our arguments in May are going to be made on constitutional grounds on the 14th Amendment’s Equal Protections Clause.”

That won’t be an easy case for the ACLU to make, Wallace said.

“That means that the only argument that Gavin Grimm has and the only argument that the plaintiffs have here in North Carolina under Title IX is that Title IX itself should be interpreted to mean gender identity rather than biological sex,” Wallace said. “Now, there’s no thumb on the scale like there was when the Obama administration interpreted its regulation to impose this duty on schools to let transgender students use facilities consistent with their gender identity.”

Wallace said that when Congress passed Title IX in 1972, no one equated the words sex and gender identity. The purpose of the law was to equalize educational opportunities between women and men, he said.

“Congress has also rejected some attempts to amend Title IX to include gender identity,” Wallace said. “A court is going to have to look at that and say that we believe, contrary to the language of the statute, contrary to its legislative history, contrary to the history of interpretation and Congress’ refusal to amend it, we think it means gender identity and not biological sex.”

Wallace also said the ACLU would have difficulty at the federal District Court level winning its equal protection argument since Schroeder last year refused to block implementation of H.B. 2 based on equal protection grounds.

Wallace said the issue of transgender rights is likely to be in the courts for a while. He said the 4th Circuit probably won’t have a decision on the case until next year. By then, it’s also likely that a ninth justice would be seated on the U.S. Supreme Court, lessening the likelihood that the high court would be deadlocked on the issue.