A federal judge in Texas on Tuesday said the Biden administration improperly attempted to rewrite a federal law barring sex discrimination in schools by applying it to LGBTQ students.

U.S. District Judge Reed O’Connor in Fort Worth, Texas, ruled in a lawsuit brought by the state’s Republican Attorney General Ken Paxton that legal guidance issued by the U.S. Department of Education three years ago was invalid because the agency lacked the power to adopt it and that it could not be enforced in Texas.

The guidance, which is not legally binding, said schools could be denied federal funding for discriminating against students based on their gender identity or sexual orientation, such as by requiring students to use bathrooms and other facilities that correspond to the sex they were assigned at birth.

A federal judge in Tennessee in 2022 had already blocked the Education Department from enforcing the guidance in 20 Republican-led states that had separately sued to strike it down. The Biden administration is appealing that decision.

The guidance was a response to a landmark 2020 U.S. Supreme Court ruling that said the federal law banning workplace sex bias extended protections to LGBTQ workers. The Education Department said the same logic applied under Title IX because the two laws use similar language.

But O’Connor in a 112-page ruling said the Education Department did not have the authority to extend that ruling to the education law, Title IX of the Education Amendments of 1972.

“To allow Defendants’ unlawful action to stand would be to functionally rewrite Title IX in a way that shockingly transforms American education and usurps a major question from Congress,” wrote O’Connor, an appointee of Republican former President George W. Bush.

The Department of Education and the U.S. Department of Justice did not immediately respond to requests for comment.

Paxton said in a statement that the ruling prevents Democratic President Joe Biden’s “effort to weaponize Title IX for his extremist agenda.”

“Threatening to withhold education funding by forcing states to accept ‘transgender’ policies that put women in danger was plainly illegal,” Paxton said.

The Education Department in April adopted formal, binding regulations applying Title IX to LGBTQ students. Tuesday’s decision does not affect those rules, which Texas and other states are challenging in court, but does suggest that they could be vulnerable to lawsuits.

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