Transgender swimmer Lia Thomas is taking legal action against World Aquatics. The governing body recently voted to limit transgender athletes’ participation in elite women’s aquatics competitions. Thomas challenges parts of the gender inclusion policy implemented on June 20, 2022.

Her focus is on overturning the rule specifying eligibility for male-to-female transgender athletes. Thomas argues that the policy discriminates against her, violating the Olympic Charter, World Aquatics Constitution, Swiss law, and human rights conventions.

World Aquatics oversees various aquatic competitions, including swimming, water polo, diving, artistic swimming, open-water swimming, and high diving.

The policy also addresses eligibility criteria for athletes previously using testosterone as part of female-to-male gender-affirming hormone treatment. The governing body pledged to create a working group for open-category events for athletes outside men’s or women’s criteria.

In August, an open category for transgender athletes was introduced at a World Cup event in Berlin. World Aquatics emphasized the event’s focus on gaining experience and celebrating diversity.

Danne Diamond of Athlete Ally criticized the transgender policy, stating it causes profound harm to trans women. The court has yet to set a hearing date for Thomas’ legal challenge.

Thomas, the first trans athlete to win an NCAA Division I title, sparked the transgender debate in swimming. Joining the UPenn women’s team in 2020, she faced criticism for an alleged “unfair advantage.”

Despite the backlash, UPenn Athletics and the Ivy League supported Thomas, and over 300 swimmers defended her ability to compete. Advocates of transgender women in sports argue that mainstream science does not support the notion of a physical advantage.