(Reuters) – A group of Democratic-led states on Thursday urged a federal appeals court to leave in place a lower court order allowing a 10-year-old transgender girl in Indiana to play on her school’s girls’ softball team, after the state legislature sought to ban transgender girls from playing on girls’ teams.

“Discrimination against transgender youth – including denying them the opportunity to participate in extracurricular activities consistent with their gender identity – can have serious health and academic consequences,” the 16 states and the District of Columbia said in an amicus brief in the 7th U.S. Circuit Court of Appeals.

Indiana’s Republican-controlled legislature passed the law in May, overriding the veto of the state’s Republican governor, Eric Holcomb, who had said it was unnecessary. Proponents of the law say that allowing transgender girls to play on girls’ teams is unfair because they have a biological advantage.

The mother of a 10-year-old transgender girl attending public school in Indianapolis then sued the school district in Indianapolis federal court, seeking to stop it from enforcing the law against her.

The girl, identified as A.M., has identified as a girl since she was four, previously played on the girls’ team and is on puberty blocking medication, according to the lawsuit. The lawsuit sought a preliminary order blocking the district from enforcing the law against her.

The Indianapolis school district itself did not oppose the injunction, but the state of Indiana intervened to defend its law. U.S. District Judge Jane Magnus-Stinson in July granted an injunction, saying in a brief order that the law likely violated Title IX, the federal law against sex discrimination in sports.

Indiana then appealed to the 7th Circuit, arguing that Title IX protects only biological sex and does not apply to gender identity.

The Democratic states, none of which prohibit transgender girls from playing on girls’ teams, said in their brief that in their experience, “allowing transgender female students to participate in women’s sports promotes inclusive school environments that benefit all and does not compromise fairness or reduce opportunities for cisgender students.”

The office of Indiana Attorney General Todd Rokita did not immediately respond to a request for comment.

A group of 19 Republican-led states filed their own brief supporting Indiana in September.

Indiana’s law is one of a flurry of measures passed by Republican-led states this year directed at transgender youth, including measures that bar classroom discussion of gender identity, block access to healthcare to help young people transition and restrict participation in sports.

The case is A.M. v. Indianapolis Public Schools, 7th U.S. Circuit Court of Appeals, No. 22-2332.

For A.M.: Kenneth Falk of the American Civil Liberties Union of Indiana

For Indiana: Solicitor General Thomas Fisher

For the Democratic states: New York Assistant Solicitor General Mark Grube and others

Read more:

Factbox: New U.S. state laws directed at transgender youth

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