(The Center Square) - The U.S. Department of Justice issued a letter to the California Interscholastic Federation, warning that its policy of requiring inclusion of transgender athletes in girls’ sports violates the U.S. Constitution’s Equal Protection Clause.

Days earlier, a transgender athlete placed first in two events at the state’s high school track and field championship, and second in another.

The letter from Assistant Attorney General Harmeet Dhillon, who heads the DOJ’s Civil Rights Division, says the rule by the California Interscholastic Federation, which governs student sports in the state, is in violation of the 14th Amendment, which prohibits discrimination on the basis of sex.

“Scientific evidence shows that upsetting the historical status quo and forcing girls to compete against males would deprive them of athletic opportunities and benefits based solely on their biological sex, in violation of the Equal Protection Clause,” wrote Dhillon.”Therefore, you cannot implement a policy allowing males to compete alongside girls, because such a policy would deprive girls of athletic opportunities and benefits based solely on their biological sex, in violation of the Equal Protection Clause.”

“As a political subdivision, you have an obligation to comply with the Equal Protection Clause,” continued Dhillon. “To ensure compliance and avoid legal liability, you must certify in writing by 5:00 p.m. ET on June 9, 2025 that you will not implement CIF Bylaw 300.D.”

Dhillon’s letter notes CIF Bylaw 300.D. requires “All students should have the opportunity to participate in CIF activities in a manner that is consistent with their gender identity, irrespective of the gender listed on a student’s records.”

The Associated Press reported over the weekend that transgender athlete AB Hernandez won first place in the CIF state high school track and field championships in the girls’ high jump and triple jump, and second place in the girls’ long jump.

In celebration of Pride Month, California Attorney General Rob Bonta Monday vowed to “recommit to fighting for the rights of LGBTQ+ people.”

“At California DOJ, we won’t back down in the face of attacks on our LGBTQ+ communities,” wrote Bonta. “We’ll keep fighting. Because no matter who you are and who you love, you deserve to be seen, heard, and protected under the law.”

CIF’s rule is in accordance with state law under Assembly Bill 1226, which requires transgender-identifying students to be allowed to participate in sports consistent with their gender identities. Under the U.S. Constitution, federal law, including the Constitution, generally trumps state law. Should the CIF not comply with the Dhillon’s letter, it may be subject to a federal lawsuit. President Donald Trump has also threatened to block federal funding over the policy, which could cost the state billions of dollars at a time of growing economic uncertainty.