This is the position the Obama administration took in 2014, when Holder released a memo stating that the Department of Justice would no longer argue that gender-identity-based workplace-discrimination claims weren’t covered by Title VII. “Although Congress may not have had such claims in mind when it enacted Title VII,” Holder wrote, “the Supreme Court has made clear that Title VII must be interpreted according to its plain text.” On his reading, the statute could rightfully include discrimination against someone simply because the person is transgender.

This position, however, is controversial. Opponents have argued that the text of the Civil Rights Act of 1964 does not explicitly include gender identity, and the government cannot enforce the law that way. This is the line Sessions took in his new memo. “‘Sex’ is ordinarily defined to mean biologically male or female,” he wrote. “Although Title VII provides various protections to transgender individuals, Title VII does not prohibit discrimination based on gender identity per se.” Based on this reasoning, Sessions has withdrawn Holder’s previous memo, noting that this is the position the DOJ will take in “all pending and future matters.”

“The Department of Justice cannot expand the law beyond what Congress has provided,” wrote Devin O’Malley, a DOJ spokesman, in an email. “Unfortunately, the last administration abandoned that fundamental principle, which necessitated today’s action.”

As it turns out, a lot of cases on this topic currently are pending. A number of high-profile cases deal with Title VII and discrimination based on sexual orientation, including a case about a skydiver recently heard before the Second Circuit Court of Appeals. The Trump administration filed a brief in that case as well, asserting a similar position: It does not see Title VII as prohibiting discrimination against gays and lesbians based on their sexual orientation.

Legal advocates on both sides tend to present the interpretation of sex discrimination under Title VII as a black-and-white issue. “They’re starting from different policy views, and when people are strongly committed to a policy view, they put a gloss on words that are more ambiguous,” said Harper. Sessions stated in his memo that the change is “a conclusion of law, not policy,” arguing that his is simply the straightforward interpretation of the statute.

The National Center for Transgender Equality and other advocacy groups, on the other hand, claim the opposite: Theirs is the correct interpretation of the law. “According to Sessions, an employer is free to hang a ‘Transgender Need Not Apply’ sign in their window,” wrote the executive director, Mara Keisling, in an emailed statement. “Fortunately, he is dead wrong on the law.”

This divide is reflected in the courts, which are split on the question of whether sex discrimination covers sexual orientation. Eventually, “the interpretation of Title VII will be decided by the Supreme Court,” Harper said.