Idaho was the first state to pass a bill limiting transgender women to compete in women's sports. It has been temporarily blocked by the federal court
New York Times quoted Lindsay Hecox, a Boise State University student and cross-country runner, saying, "the bill marginalizes transgender athletes like herself".
Associated Press reported that after the Idaho bill was passed, the American Civil Liberties Union (ACLU) filed a lawsuit in federal court challenging the law. In August 2020, the court issued a temporary injunction to stop Idaho from enacting the law barring transgender girls and women from participating in women's sports. U.S. District Judge David Nye said, "the law's ban on transgender athletes stands in stark contrast to the policies of elite athletic bodies that regulate sports both nationally and globally." He furthers adds that "the preliminary injunction was justified because the plaintiffs were likely to win in court."
Idaho became the first U.S. state to ban transgender women and girls from participating in female sports leagues and changing their birth certificates. However, a federal court blocked the bill before enacting it.