Colorado Propositions 134 and 135 both passed. The Associated Press called Prop 134 at 4:12 p.m. Thursday, Colorado Newsline reported, and called Prop 135 for the yes side Friday morning, The Denver Gazette reported. Together they write new limits on transgender students’ school sports and on surgery for trans minors into state law. “This measure shall become effective on January 1, 2027,” the text of Prop 134 says, and Prop 135’s text sets the same date.
With an estimated 96% of votes counted, AP results on PBS showed the yes side ahead by 4.7 percentage points on Prop 134 and 4.1 points on Prop 135. Prop 135 “prohibits surgeries on minors that would alter their biological sex characteristics as a treatment in response to a minor’s perception of sex or gender,” according to its Blue Book entry.
Families Not Politics, the coalition that fought both measures, said it will “exhaust every option” to defend trans kids’ rights and “keep working toward a Colorado where transgender students are allowed to be kids, not political symbols,” Colorado Newsline reported. “To every transgender kid and family, we’ve got your back,” Bruce Parker, executive director of Rocky Mountain Equality, said in a statement. “This is your home too. This vote doesn’t change that.”
Jax Gonzalez, political director of One Colorado, said opponents “used fear and confusion to make scapegoats of trans young people.” “This outcome is painful, and it will have real consequences for young people and families across our state,” Nadine Bridges, the group’s executive director, said in One Colorado’s statement.
Erin Lee, executive director of Protect Kids Colorado, aimed her statement Wednesday at state leaders. “And today, we are sending a clear signal to Colorado’s leadership: when elected officials fail or refuse to protect kids, We the People will come together and do it ourselves,” she said. After the Prop 135 call, she wrote on X, “We won. Girls won. Kids won,” The Denver Gazette reported.
Under Prop 134, every school team must be designated “as being for biological males or biological females only, or as mixed,” the Blue Book voter guide says. “In a deep blue state, with a deep blue election wave, the voters said: Protect girls’ sports,” Jennifer Sey, a former gymnast who helped lead the Prop 134 campaign, said while ballots were still being counted, according to Chalkbeat Colorado.
When Colorado Propositions 134 and 135 Take Effect
Both are statutes, not constitutional amendments, and an initiated law becomes official once the governor proclaims the vote, “not later than thirty days after the vote has been canvassed,” Article V of the state constitution says. “We’re going to have to take a look at these anti-trans measures, and what adjustments are necessary and appropriate,” Gov.-elect Phil Weiser said Wednesday near the Capitol, Colorado Newsline reported.
Weiser, who signaled a willingness to back legislative changes, doesn’t take office until Jan. 12, and the secretary of state must certify statewide results by Nov. 30, a Brennan Center guide says, so the proclamation falls to Gov. Jared Polis.
Prop 134 Never Says How a School Should Prove Sex
“The measure does not impose a specific method for determining or demonstrating biological sex,” the Blue Book says. Its text defines a female as a person “whose biological reproductive system is organized around the production of ova.”
“I don’t believe it would be acceptable for Colorado to have every student athlete have to go through full-body examinations or other invasions of privacy,” Weiser said Wednesday.
The sports law covers public and private K-12 schools and colleges, though youth teams run by private clubs or leagues fall outside it, Chalkbeat reported. “There are kids in the state who, if this passes starting in January, they may not be able to play with their friends if they’re 6 years old,” Bruce Parker, executive director of Rocky Mountain Equality, told KKTV before the vote.
A student the law counts as female can join a boys’ team only if no girls’ team is available, the ballot title says, which leaves trans boys facing limits too. “So any young person, transgender or not, will be impacted by this,” Nadine Bridges, executive director of One Colorado, told Chalkbeat in October.
When a public school district ignores the law, the education commissioner “must first notify the district of its noncompliance,” the Blue Book says, and the measure sets no enforcement mechanism for private K-12 schools, colleges or athletic associations.
Does Prop 134 Override the Colorado Anti-Discrimination Act?
“Public K-12 schools, colleges, and universities may not exclude students from extracurricular activities that align with their gender identity, even if their gender identity is different from their biological sex,” the Blue Book says of the Colorado Anti-Discrimination Act. Prop 134 bars government bodies, licensing and accrediting groups and athletic associations from even entertaining a complaint against a school for keeping a separate girls’ team.
“It is unclear at this time how the measure will impact current state law,” the Blue Book says.
HB25-1312, the Kelly Loving Act that Polis signed May 16, 2025, added “chosen name and how the individual chooses to be expressed” to the law’s forms of gender expression, the legislature’s summary says.
Bridges said advocates would do extensive legal analysis if Prop 134 passed, looking for any way forward for trans athletes, Chalkbeat reported. “We’re going to exhaust all possibilities to ensure that our young people can be involved in what they want to be,” she said.
Prop 135 Bans Surgery and Insurance Coverage for Trans Minors
Prop 135 covers anyone under 18, and its text reaches health care professionals and anyone else who knowingly performs or provides the surgery. “The measure bans the use of state or federal money, Medicaid reimbursements, and private health insurance to pay for the prohibited surgeries,” the Blue Book says.
Children’s Hospital Colorado, Rocky Mountain Children’s and Denver Health, the state’s three large pediatric surgical providers, “report that they do not perform gender- or sex-based surgeries on transgender patients under 18 years of age,” the booklet says. Hormone therapy and puberty blockers fall outside the measure, CBS News Colorado reported.
“The measure may also limit other surgeries for minors, including non-transgender minors, if the treatment is interpreted as being in response to the minor’s sex or gender perception,” the Blue Book says.
“It’s just common sense protections for kids,” Lee told KKTV in October. “In Colorado, there is a core value of privacy and bodily autonomy,” Parker told the station.
Prop 134 and the Supreme Court’s June 30 Sports Ruling
The U.S. Supreme Court upheld West Virginia’s and Idaho’s bans 6-3 on June 30, ruling in West Virginia v. B.P.J. and Little v. Hecox that neither Title IX nor the Equal Protection Clause stops schools from setting girls’ sports eligibility by “biological sex,” JURIST reported. Justice Brett Kavanaugh’s majority opinion called “safety and competitive fairness” important government interests.
“Basic truth and biological reality don’t have a party,” said Sey, who argued the likely passage should inspire other Democratic-led states, according to Chalkbeat.
Washington, Nebraska and Arizona voters weighed trans athlete measures too, Yahoo News reported, and Washington’s Initiative 638 passed, Gayety reported. Gayety’s results hub tracks the rest. “We’re right here with you and we love you,” One Colorado wrote Wednesday on Instagram, posting a video while votes were still being counted.
