A group of parents, educators, civil rights attorneys, and LGBTQ+ advocates are challenging Initiative 638 in court.

I-638 bars trangender girls from playing girls’ K-12 sports in Washington state. It’s set to pass with 56% of the vote, after last week’s midterm election.

On Monday night, opponents represented by the ACLU of Washington, Legal Voice, and Pacifica Law Group, sued the state to stop the measure from going into effect.

The plaintiffs in the case are five families with daughters who play school sports, including two trans girls. The state’s largest teachers union, the Washington Education Association, and a non-profit that supports families with transgender children, called TransFamilies, are also plaintiffs in the case.

The suit alleges the initiative, specifically the sex verification process, violates the Washington state Constitution and students’ right to privacy.

Washington state also includes gender identity and expression in its anti-discrimination law. Adrien Leavitt, staff attorney at the ACLU of Washington, told KUOW’s “Soundside” the initiative would require amending that law.

“The initiative needs to be transparent that it is amending the Washington Law Against Discrimination and permitting discrimination against transgender girls, and that was not a part of the text,” Leavitt said.

Darren Littell, executive director of Let’s Go Washington, which backed I-638, argued the sex verification claims were based on “false assumptions.”

Littell said doctors are already aware if a kid is trans, and that info can be communicated to schools without violating a student’s privacy.

“ What we’ve seen work in other states is just saying, ‘Is this individual eligible for girls’ sports, yes or no,’” Littell said. “That has nothing to do with releasing any kind of private information. All it does is say whether or not that person is eligible for girls’ sports.”

The law is set to go into effect on Dec. 3. The legal team bringing the lawsuit to stop it is asking for an emergency injunction as the case proceeds, meaning the measure would not go into effect while it’s being litigated.

The Washington Attorney General’s Office will be tasked with defending the initiative.

Libby Denkmann, David Kroman, Hans Anderson are reporters for KUOW. This story comes to you from the Northwest News Network, a collaboration between public media organizations in Oregon and Washington.

It is part of OPB’s broader effort to ensure that everyone in our region has access to quality journalism that informs, entertains and enriches their lives. To learn more, visit our journalism partnerships page.

News Source : https://www.opb.org/article/2026/11/11/washington-state-lawsuit-filed-stop-initiative-banning-transgender-girls-sports/