The debate about trans athletes in women's sport has become one of the loudest in public life, and almost none of it is about evidence. I want to change that. What we actually know about performance, physiology, and fairness is more complicated and more interesting than the headlines suggest, and the legal cases being fought in the United States right now are being decided in a climate of panic, not data.
What is actually being argued in the SJSU and wrestling lawsuits?
The lawsuits circulating in this space, most visibly around San José State University volleyball and cases involving wrestling, follow a consistent pattern. A trans woman competes. Opponents or their families file a legal challenge arguing her inclusion is inherently unfair. The court is asked to decide, under Title IX or state-level sports bans, whether the trans athlete's participation constitutes sex discrimination against her teammates or opponents.
What almost never features in these cases is any specific evidence that the individual athlete concerned gained a measurable competitive advantage. The argument is almost always structural and categorical: she is trans, therefore the inclusion is wrong, therefore every loss sustained by a cis woman in that competition is attributable to that fact. That is not a scientific claim. It is an assertion presented as one.
In the SJSU case, which attracted enormous national attention, the university's trans volleyball player was subjected to boycotts, online harassment, and the kind of organised legal pressure that would break most people. The evidence presented that she had performed at an unfair advantage over her teammates or opponents was thin. What the case produced in abundance was hostility.
How does the evidence on physical performance actually read?
The physiology here is real, and it deserves honest engagement. Testosterone drives many of the physical differences that create male-pattern athletic advantages: muscle mass, lung capacity, bone density, haemoglobin levels. Those are not myths. But the story does not end there, and it does not end with transition either.
What the research shows, to the extent that good-quality research exists on trans athletes at all, is that hormone therapy substantially reduces most of these markers. Muscle mass decreases. Haemoglobin drops. The timescale matters, and varies by individual, but after sustained hormone therapy the gap between a trans woman's physiology and a cis woman's physiology narrows considerably. The International Olympic Committee acknowledged this in its 2021 framework, moving away from testosterone thresholds and towards individual, sport-specific assessment, precisely because the old model was not supported by the evidence.
What the research also shows is that athletic performance is enormously varied within any category we choose to draw. A six-foot-two cis woman has physiological advantages over a five-foot-two cis woman in basketball. A woman with naturally elevated testosterone, common in elite athletes, has physiological advantages over her competitors. We do not ban these women. We accept that sport involves physical variation, and we organise competition around it imperfectly, as we always have.
The claim that any trans woman in any women's sport is inherently unfair to every cis woman around her is not supported by what we know. It is an ideological position that uses the language of science without its rigour.
Why is this conversation so hostile, and who does that hostility serve?
I have been watching the culture-war machinery around trans sport for years now, and I want to say something plainly. The hostility in this debate is not primarily driven by genuine concern for women's sport. If it were, we would see the same energy directed at the chronic underfunding of women's athletics, the pay gaps between elite women's and men's competitions, the lack of broadcasting coverage, the coaching and governance inequalities that have shaped women's sport for decades. We do not. The outrage arrives with precision, targeted at trans women, and moves on.
That targeting does real harm. Trans athletes, almost all of whom are competing at amateur and recreational levels, not elite international ones, are subjected to harassment, legal challenges, boycotts, and a sustained public message that they do not belong. Many leave sport entirely. The research on trans people and physical activity tells us consistently that sport is vital to wellbeing for trans people, as it is for everyone, and that exclusion from it causes significant harm.
The high-engagement hostile content framing that drives this story online treats individual trans athletes as symbols of an ideological battle. They are not symbols. They are people who want to compete, to be part of a team, to do something physical that brings them joy. When we lose sight of that, we have already lost the ethical thread of the conversation.
What do the governing bodies actually say?
Sports governance on this question is genuinely mixed and genuinely evolving. World Athletics and FINA (now World Aquatics) have moved towards tight testosterone restrictions or, in swimming's case, effectively barring trans women from elite competition entirely. The IOC took a different approach, emphasising inclusion and asking individual federations to develop evidence-based policies rather than issuing blanket rules. World Rugby banned trans women from elite play on precautionary safety grounds, which is a defensible position in a high-contact sport with different physical risk dynamics.
None of these positions should be read as a settled scientific consensus. They are governance decisions made under political pressure, with variable quality of evidence behind them. The policies vary by sport, by level of competition, and by federation. What holds across almost all of them is a distinction between elite international competition, where the stakes are high and the numbers tiny, and recreational and amateur competition, where trans inclusion causes no measurable problem at all and exclusion causes immediate, concrete harm to real people.
The legal cases in the United States are largely about school and collegiate sport, not Olympic competition. Treating them as if the elite physiological arguments automatically transfer down to a school volleyball league is a category error that the litigation is using strategically.
What does fairness in sport actually require?
Sport has never been perfectly fair. It has always involved a negotiation between the physical variation that makes competition interesting and the structural rules that make comparison meaningful. We draw those lines constantly, imperfectly, and we redraw them as knowledge evolves.
What fairness requires in sport is not the elimination of every possible source of variation. It is the design of competition that gives people a meaningful chance to participate and to find out what they can do. For most trans athletes, most of the time, inclusion does that. Exclusion does not.
I am not dismissing the genuine complexity at the elite end. At the very top of international competition, where margins between athletes are tiny and careers depend on them, the questions of physiology and advantage require careful, sport-specific, evidence-based assessment. I accept that. What I will not accept is the casual transfer of elite-level anxiety to every level of every sport, deployed as a political weapon against ordinary trans people who just want to play.
What should we actually be asking?
When a legal case or a governing body policy lands in the news, these are the questions worth asking: what level of competition does this cover? What specific evidence of advantage was presented? What harm to trans athletes was weighed against the claimed harm to cis athletes? Was the decision made under political pressure, or in response to peer-reviewed evidence? Who benefits from the exclusion, and who is harmed by it?
Those questions cut through the noise. They are not the questions the litigation or the hostile content is designed to prompt. They are the questions that take trans athletes seriously as athletes, and as people.
Trans women in women's sport are not a threat to women's sport. The underfunding, the governance failures, and the political weaponisation of this debate are a threat to women's sport. I know which one I am more worried about.