A Montana Supreme Court just ruled that the state cannot enforce its own law defining sex as male or female — and five justices couldn’t explain what a “woman” actually is.

Story Snapshot

• A 5-2 Montana Supreme Court ruling blocked the state from enforcing its binary sex definition on birth certificates and driver’s licenses.
• Montana passed a law defining sex as strictly male or female across more than 60 sections of state law — the court put that on hold.
• The majority called transgender discrimination a form of sex discrimination under the Montana Constitution.
• The case is still ongoing in lower court — this ruling only preserves the status quo while the legal fight continues.

Montana’s Court Rewrites the Meaning of Sex

In a 5-2 decision, the Montana Supreme Court upheld a lower court order blocking the state from enforcing policies that define sex as binary on government identity documents. The ruling means transgender residents can still change the sex listed on their birth certificates and driver’s licenses while the case moves forward. The American Civil Liberties Union of Montana called it a major win, saying the court recognized that “transgender discrimination is, by its very nature, sex discrimination.”

The majority also declared that being transgender is a “suspect class” under Montana’s constitution. That legal label raises the bar the state must clear to defend its own laws. Critics on the right see this as judicial overreach — five justices using activist logic to override a law that voters’ elected representatives passed through the normal process. The two dissenting justices did not agree, though the full dissent has not been widely published in available reporting.

🙄 AAF’s June Dishonorable Judicial Conduct Award recognizes five Montana Supreme Court justices for imposing their flawed views on sex and gender—disregarding biology, reality and the law.

Read more from @HansvonSpakovsky and @TomJipping: pic.twitter.com/Ec518x7r5j

— Advancing American Freedom (@AmericanFreedom) June 17, 2026

Montana Lawmakers Defined Sex Clearly — Courts Disagreed

Montana’s legislature passed a law tying the legal definition of sex to biology and reproduction, recognizing only male and female. That law applied to more than 60 sections of state code, including rules for driver’s licenses and marriage licenses. Governor Greg Gianforte signed the bill into law. Supporters said it simply gave state law a clear, consistent definition — one rooted in biological fact, not personal identity.

The courts have now blocked that law more than once. A prior version was struck down on procedural grounds. The latest version ran into the same wall when a district court found it likely violated Montana’s anti-discrimination protections. The state has now lost these fights at multiple levels, creating what critics call a pattern of courts substituting their preferences for the legislature’s clear intent. The state’s legal rationale — including any fraud-prevention or records-keeping arguments — has not been fully aired in public reporting.

This Is Part of a Bigger National Battle

Montana is not alone. Similar fights are playing out across the country over who controls the sex marker on government documents. President Trump signed an executive order in January 2025 directing federal agencies to recognize only biological sex. That order affected U.S. passports, but the U.S. Supreme Court later paused a lower court ruling that had blocked it, meaning new passports now list birth sex again. State battles, like Montana’s, remain separate and are decided under each state’s own constitution.

The Montana ruling is a temporary block, not a final verdict. The underlying case is still being decided in district court. That matters because some coverage has described the ruling as striking down Montana’s sex-definition law entirely — that is not accurate based on available reporting. What the court did was preserve the old policy while the legal fight continues. Still, five justices signaling that Montana’s binary sex law likely violates the state constitution is a serious blow to common-sense governance. Conservatives watching this case should understand: the fight is not over, but the courts are not making it easy for states to defend basic biological definitions of sex.

Sources:

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