Lia Thomas, a trans US diver, is suing to reenter the competition.

Lia Thomas, a US swimmer who became the first transgender swimmer to win an NCAA college championship, is suing the law in an effort to reenter the world’s most prestigious women’s sports, including the Olympics.

Since World Aquatics implemented new rules in 2022 that exclude anyone who has gone through “any part of male puberty” from the female category, Thomas hasn’t been swimming. Transgender girls could compete before that if they controlled their hormone levels.

World Aquatics claimed that even after taking drugs to lower their hormone levels, swimmers like Thomas continued to experience major physical benefits from going through male puberty, including endurance, power, speed, strength, and lung size.

Thomas, who before transitioning was a modest swimmer in the male category, has presently hired Canadian law firm Tyr to represent her in an arbitration case for sport in Switzerland. However, it is understood that the case is extremely unlikely to be heard before the Paris Olympics because the 25-year-old is not currently registered with US swimming.

The decision, which was made public by the Daily Telegraph, represents the most recent development in the contentious argument between those who contend that fairness and safety in women’s sports are of the utmost importance and others who maintain that the participation of transgender athletes should be given top priority.

Thomas has consistently refuted the idea of transitioning for an advantage. Thomas remarked in 2022, “The biggest misunderstanding, I think, is the reason I transitioned.” People may say, “Oh, she only transitioned so she could have the upper hand and win.” I transitioned in order to be happy and true to myself.

Brent Nowicki, the executive director of World Aquatics, defended its female participation policy in a statement on Thursday, saying that it “was strictly developed on the basis of advice from leading medical and legal experts, and in careful consultation with athletes.”

He continued, “World Aquatics remains absolutely committed to protecting women’s sport and remains confident that its female inclusion policy represents a fair approach.”

Thomas has not yet commented, but different governing bodies will keep a close eye on what happens next. Rugby, athletics, and cycling have all recently been among those sports to impose stricter regulations, so a victory for Thomas would leave them vulnerable to legal repercussions.