School sports can be an enjoyable or important part of a young athlete’s life. Prop 134 seeks in part to prevent trans girls from competing against cisgender girls.

At its simplest, passing Proposition 134 (formerly Initiative 109) would first require school-based athletic teams to be designated as either for biological men or boys, biological women or girls, or that they’re co-educational and open to athletes of any gender. While there are other points, perhaps the most pertinent second point is that 134 would prohibit a “male student or participant” from participating on a girls’ or women’s team in Colorado. Schools would be required to create a policy to conform with this new law if 134 passes, and schools could be disciplined for failing to comply.

Prop 134 is a statutory measure, not Constitutional, and would pass with a simple majority of 50% (plus one) of the vote.

Key Points About Prop 134

The “at its simplest” paragraph above might touch on the three most important general points in Proposition 134. Here are a few others:

  • Prop 134 would apply to interscholastic or intramural sports in elementary schools, middle / high schools, or “postsecondary” institutions like colleges or universities.
  • Girls or women would also not be allowed to participate in boys’ or men’s sports unless there isn’t a girls’ or women’s team available to them at the school.
  • The language in 134 would not prevent people of any gender from participating on teams designated as “mixed” or “co-educational.”
  • If a school does not comply with Prop 134, the state Commissioner of Education must notify the school district and allow it “reasonable time” to comply. If it still does not comply, the language in 134 says “the Commissioner shall take appropriate remedial action,” but 134 does not define what that action might be.

Why Proposition 134?

The issue of people who were born as biological males, but became transgender women, and decided to participate in competitive girls’ or women’s sports has been in the news lately. To some extent what made the news might have been about politicians attempting to use it as a political wedge issue, but some cisgender girls or women have had the experience of competing against trans athletes and have spoken out against it.

The Prop 134 designated representatives, Erin Lee and Michele Austin, launched an issue committee called “Protect Our Children,” plus they are also the designated representatives for this year’s Proposition 133 (stronger penalties for human trafficking of a minor) and 135 (prohibiting sex-altering surgeries on minors).

Erin Lee has spent years in activism questioning gender fluidity. Readers might gain perspective from a Colorado Public Radio story, linked here, about Lee’s experience with a daughter who at one point told her parents she was transgender. Michele Austin is described in Colorado Times Recorder as being a “longtime Republican strategist” who owns a consulting firm called “Red Map Strategies.”

On June 30, 2026, the U.S. Supreme Court basically ruled that states can exclude biological men from women’s sports. “Respondents acknowledge that States may exclude most biological males from women’s and girls’ sports, given the general physical differences between males and females.” Prop 134 was drafted and cleared for the Colorado ballot before this Supreme Court ruling, but the information in the ruling might be relevant for discussion on this initiative.

At times, citizen initiative proponents might run ballot measures if the state legislature can’t or won’t pass a bill to codify what they’re after. At least two state bills, HB 23-1098 and HB 26-1083, had similarities to Prop 134, and were both defeated in legislative committees on 8-3 straight-party line votes with Republicans in support and Democrats in opposition.

While the Colorado High School Activities Association (CHSAA) has a three-page long “Transgender Policy Statement,” passing Prop 134 would put its language into state law.

Do Trans Girls Compete in School Sports?

Without great statistics to prove how often it happens, it is possible for trans girls to compete in girls’ high school sports.

In 2026, Yahoo News and other sources reported: “Jurupa Valley High School senior, AB Hernandez, 17, captured first place in the girls’ long jump, high jump and triple jump events during the California Interscholastic Federation’s Southern Section championship final.” In the long jump, Hernandez beat her closest competitor by about 1’5”.

Or, in women’s sports, this story details some of the controversy around Lia Thomas, a trans woman who competed in swimming events for the University of Pennsylvania and was a dominant performer.

But whether there are large numbers of trans athletes participating in girls’ sports is a tough issue to prove. The website transathlete.com claims that “there is no evidence” of large numbers participating, and there is “no statistical support” showing that trans athletes are dominating.

Readers seeking deep scientific analysis on whether trans athletes have advantages over cisgender athletes might want to search other sources. But here’s a link to a story citing a study that says there is no inherent advantage, and the story includes a link to the study.

What is Colorado’s K-12 Policy Now?

The paragraph and two bullet points below are copied from the “Lawyers for Good Government” website, which has an interesting page explaining a number of situations regarding transgender legal issues, not only about trans athletes.

“Although Colorado has not implemented any laws banning transgender people from playing in sports that align with their gender identity, according to the Colorado High School Activities Association (CHSAA), transgender students must inform their school in writing if their gender identity is different from the one assigned at birth. The school then conducts a confidential evaluation to decide which team the student can join.

  • The following criteria may be used to determine participation: (i) current transcript and school registration information and (ii) a written statement from the student affirming their gender identity.
  • Transgender athletes have the right to participate in sports, but the school’s evaluation determines if they can play on the team that matches their gender identity. The school can request, but not demand, health records or hormone therapy details. The CHSAA can review the school’s decision and potentially overrule it to ensure compliance with their approved policies. The families can appeal to the state association if they disagree with the decision.”

There is a full listing of CHSAA bylaws and policies at: Colo. High Sch. Activities Ass’n, CHSAA Transgender Inclusion Bylaw & Policy (2019).

Proponents: The committees “Protect Kids Colorado – Issue Committee” and “Protect Our Children” have registered to support Prop 134.

  • Protect Kids Colorado had reported $116,450.84 in total contributions, while
  • Protect Our Children had not reported any contributions.

Opponents: Five committees have registered to oppose Prop 134.

  • Families Not Politics had reported $1,656,364.98 in total contributions as of Oct. 6, including ACLU for $297,601.98, COBALT for $224,000, One Colorado Education Fund for $134,500.84, Brighter Future for Colorado for $110,000, ACLU Foundation for $98,664.46, and Planned Parenthood Action Fund for $100,000.00. Both the ACLU and Planned Parenthood funds had New York City addresses.
  • Vote Common Sense is opposing 134, but also 132, 133, 135, and 136 along with Amendments 81, 82, 84, and 85. It’s reported $646,500 in total contributions as of Oct. 6, including $200,000 from Washington, DC-based Green Advocacy Project, $100,000 from Merle Chambers of Denver, $65,0000 from Colorado Fund for Children & Public Education, $50,000 from Coloradans for Real Safety Solutions, $50,000 from Colorado Immigration Rights Coalition, $50,000 from Colorado WINS, and $35,000 from COBALT.
  • The People’s No opposes 134, but also 132, 135, and Amendment 81. It’s reported $200,000 in monetary contributions as of Oct. 6, and $51,246.11 non-monetary, including $246,346 from ACLU of Colorado, and $103,332 from COLOR Action Fund.
  • No on 109 and 110 had reported $10,787.68 in contributions.
  • Protect Trans Kids had not reported any contributions yet.

Links to More Information:

Richard’s Take

I’ll vote “no” on Proposition 134 because I don’t think the law it proposes is necessary and I don’t have any reason to believe Colorado has a major problem at this time, but I can see to some extent why it came up.

I’ve skimmed a fair amount of literature suggesting that trans girls or women are not necessarily going to be better athletes in given sports than cisgender girls or women. I’ve also learned that girls or women are also not necessarily inferior to boys or men in sports across the board. I remember the first time a woman beat me in a sport that I thought I was pretty good at, when I was young and in very good shape. Obviously, any of today’s WNBA players and probably most women’s major college basketball players would have mopped up the floor with me in my prime, even back when I practiced daily.

But what really happens when the issue really is a matter of size or strength? Let’s say a 220-pound person who transitioned wants to play defense on the girl’s hockey team. I’d be a little troubled by that, not only because of a possible sporting advantage, but also because of the possibility for injury. Or, what about a 6’10” basketball/volleyball player, both sports in which height can really matter? (And I understand that these examples are outliers, but “outlier” doesn’t mean “impossible.”)

Being many decades removed from my high school sports days, I don’t really care anymore about what happened back then. But at the time, it mattered to me. I have no doubt school sports matter to a lot of today’s youth as well. It’s a test of your ability, competition can be visceral, and some athletes might be competing for awards or even college scholarships. I would have complained to the heavens if someone with unfair physical advantages took an award or something important from me, so I have some sympathy for those who believe they’re in unfair competition today.

I’ll vote no on Prop 134, but would support keeping an eye on the issue in Colorado to help make sure there aren’t too many legitimate complaints about athletes facing unfair competitive conditions. If it crosses a line that I can’t define yet, there might be reason to revisit. I do support trans rights, and they’re people who might absolutely love competitive sports, like any person who loves competitive sports. But cisgender girls or women have rights too, plus in some cases dreams or desires of being at the top of whatever sport they’re involved in. Whether Prop 134 wins or loses, we probably haven’t heard the last of the general issue.