Billie Jean King, Megan Rapinoe and Candace Parker Support Brief Against Idaho Anti-Transgender Law

Briefs were filed Monday in support of Hecox v. Little, a challenge to Idaho's law banning transgender athletes from participating in women's sports in school.

Several amicus briefs were filed Monday in support of Hecox v. Little, a challenge to Idaho's law banning transgender athletes from participating in women's sports in school.

Tennis icon Billie Jean King, World Cup champion Megan Rapinoe and WNBA legend Candace Parker were among the more than 175 athletes who joined Athlete Ally and the Women's Sports Foundation in signing a brief filed by Lambda Legal with the U.S. Court of Appeals for the Ninth Circuit. The brief highlights the athletes' beliefs in the importance of equal opportunity for girls and women to participate in sports at all levels. 

“There is no place in any sport for discrimination of any kind,” King said. “I’m proud to support all transgender athletes who simply want the access and opportunity to compete in the sport they love. The global athletic community grows stronger when we welcome and champion all athletes—including LGBTQI+ athletes.”

In March, Idaho enacted the Fairness in Women's Sport's Act (HB500)—the first of its kind nationwide. Girls and women who compete in youth, high school and college sports, whether they're transgender or cisgender, will be subject to being challenged by competitors on their biological sex—in essence, forced to prove their womanhood. If found to not be "female," they would not be able to compete with girls and women.

The following month Lindsay Hecox, a Boise State student who is transgender, filed a lawsuit alongside the ACLU and a Jane Doe to challenge the HB500 law. In August, U.S. District Judge David Nye granted a preliminary injunction against the enforcement of the law.

“I love running, and part of what I enjoy about the sport is building relationships with a team. I’m a girl, and the right team for me is the girls’ team,” Hecox said in a statement. “It means a lot to me that so many people are on my side and supporting me.”

Hecox hopes to compete with the Boise State women's cross-country team but would be barred by Idaho law, even though NCAA rules allow it. She has emerged as an activist for transgender rights in Idaho and across the country in recent months, often appearing at the Idaho statehouse for rallies, testimony and other community organizing, per Sports Illustrated's Julie Kliegman. 

On Monday, the National Women's Law Center and more than 60 other women's rights and civil rights groups also filed an amicus brief asserting the HB500 law "targets women and girls who are transgender and [deprives] them of the benefits of participating in sports violates the Equal Protection Clause of the U.S. Constitution." Transgender athletes, companies including Nike and Ben & Jerry's, three former Idaho attorneys general, the intersex advocacy group interACT, coaches and administrators, and the American Medical Association and other medical associations all filed briefs, as well.

The court has not yet set a date for oral argument.