Mississippi has become the first state to pass a law under the Biden administration banning transgender women and girls from playing on women’s sports teams. Gov. Tate Reeves signed the bill into law Thursday despite courts striking down similar legislation in Idaho last year. Nearly half of U.S. states are attempting to ban transgender children from freely participating in sports or accessing health care, a reaction to President Biden’s executive order that explicitly prohibits discrimination in schools on the basis of gender identity. Reeves said in a March 4 tweet the law’s intention is to “protect young girls from being forced to compete with biological males for athletic opportunities,” but an ACLU lawyer focused on transgender rights called the law “very vague and seemingly unenforceable.”

Chase Strangio, Deputy Director for Trans Justice with the ACLU LGBTQ & HIV Project, said the bill would “hurt Mississippi’s economy but most upsetting, it will hurt transgender youth in Mississippi. We call on the Biden administration to ensure our federal civil rights laws are fully enforced—including those that protect transgender youth from discrimination in schools... This bill is not about sports. It’s about pushing trans people out of public life.”