In the Trump administration's latest assault on transgender Americans' rights, the Justice Department on Wednesday urged the U.S. Supreme Court to rule that employers are legally permitted to discriminate against transgender workers—potentially rolling back a lower court's ruling that was celebrated by LGBTQ rights groups earlier this year.

As the Supreme Court decides whether to rule on a 6th Circuit Court of Appeals case from last March, which found that transgender Americans must be protected under federal anti-sex discrimination laws, the DOJ explicitly argued that such protections should not be extended to a group that the Trump administration has essentially stated does not exist and should not be acknowledged.

"The ordinary meaning of 'sex' does not refer to gender identity," Solicitor General Noel Francisco wrote in a brief, according to Bloomberg Law. The argument was in keeping with the administration's official position on transgender people, made public earlier this week: that one's gender is dictated not by one's identity, but by sex assigned at birth.

Like the administration's earlier announcement, the news of the brief sparked outrage among LGBTQ rights advocates.

The administration's narrow definition of gender, wrote Robin Carver at Common Dreams this week, "flies in the face of the broad consensus of the medical community that treats trans people and worldwide standards for trans health care."

"It's a fundamental denial of our most basic and important claim: that our sex and gender cannot be accurately identified at or before birth, and they are not sufficiently explained by a binary of female/male, woman/man, or XX/XY," she added. "It's the policy equivalent of telling trans people that we don't exist. It's flatly absurd." 

The DOJ's brief was filed regarding the case of Aimee Stephens, who was fired from her job at a Detroit funeral home after telling her employer that she was transgender.

The LGBTQ civil rights organization Lambda Legal, which filed an amicus brief in the appeals court in support of Stephens, expressed hope that the high court would rule in favor of the 6th Circuit's earlier decision, while the ACLU pledged to fight the Trump administration's "hate-filled position" in the Supreme Court.

"They can say what they're going to say, but the courts will have the final word," Greg Nevins, an attorney for the group, told Bloomberg Law.