A Montana judge on Wednesday struck down a state law defining sex in binary terms, finding that the law violated the Montana Constitution’s guarantees of equal protection and privacy.

Judge Leslie Halligan of the Montana Fourth Judicial District Court, Missoula County, denied the state’s motion for summary judgment and held that the plaintiffs, a group of transgender, intersex, and Two-Spirit Montanans, had standing to challenge the law’s constitutionality. She stated: “By declaring as a matter of law that a human being can only be ‘exactly’ one of two sexes, SB 458 explicitly excludes [two plaintiffs] from the definition of human beings, causing immediate harm.”

Judge Halligan then granted the plaintiffs’ motion for summary judgment, declaring the law “facially unconstitutional” and enjoining the state from enforcing the law or any legislation with similar effects.

Senate Bill (SB) 458, which was passed by the state legislature in 2023, established definitions for the terms “female,” “male,” and “sex” as used in the Montana Code. Halligan found that the definitions created a “gap” for individuals whose gender identities do not align with their biological sex and thus violated the guarantee of equal protection under the Montana Constitution.

She further held that the law violated the state constitution’s right to privacy, stating:

By restricting the definition of sex in a manner which interferes with even that of a doctor and patients’ definition, SB 458 prohibits the individualized care and exercise of professional medical judgment which should be afforded to the individual, in violation of the right to privacy.

Montana is one of many US states that has passed legislation targeting the LGBTQ+ community in recent years. According to the Movement Advancement Project (MAP), 25 states across the country have enacted legislation banning gender-affirming healthcare for transgender youth. Other state-level legislation includes bans on books with LGBTQ+ themes in schools, prohibitions on transgender girls from playing on girls’ sports teams, and restrictions on trans students using school restrooms and facilities that correspond with their gender identity. The ACLU is currently tracking 390 anti-LGBTQ bills across the US.

At the federal level, President Donald Trump recently issued an executive order directing federal agencies to restrict access to gender-affirming medical care for transgender youth under age 19 and block federal funding for such programs. Two federal judges have since temporarily blocked the order. Trump also signed an executive order banning transgender people from serving in the US Armed Forces, and a federal judge will decide whether to temporarily block the order by early March.

The US Supreme Court will rule on some of these issues facing the LGBTQ+ community soon. The court, for instance, recently agreed to decide whether Maryland parents can exempt their children from reading elementary school books involving LGBTQ+ topics. The court will also rule on the legality of state bans on gender-affirming healthcare for transgender minors.