Thread by @Scienceofsport

The paradox in action. Illegal advantage in the 400, legal in the 200. The reason this weirdness exists can be traced back to the CAS Chand decision in 2016, and the “narrow” framing of evidence for the DSD policy, but this situation was inevitable. The events are too similar

https://twitter.com/jgault13/status/1422030999840378882

Ok, brief explanation. In 2016, the policy for DSD athletes covered all events. Chand challenged it, and CAS said they understood the rationale for the policy, but it required evidence. WA were thus mandated to find the evidence. They tried, but did a poorly conceived study that

…looked for an association between T and performance in each event. They found a positive association in the 400m, 400m H & 800m, and actually a negative on in the 100m! But the policy was thus revised to cover those events, plus the 1500m, as it was deemed similar to 800

It left all other events off, because at the time of the study, no association between T and performance could be found. That’s almost entirely because no DSD athletes competed in those events, which speak to the circular nature of the attempt to find the evidence. In any event,

…the policy was revised and upheld when Caster Semenya challenged it. It leaves this weird paradox where we KNOW that T confers advantages in ALL events, but the policy implies it exists only in some events. Thus an athlete is legal one day, illegal the next, depending on event

The policy did, however, say that in future other events may be added as evidence emerges. Presumably a DSD athlete winning an Olympic medal will constitute “evidence”, but it’s a messy situation, one that appears to target success, rather than principle or physiological theory

Which is strange, because the WA policy that was eventually defended at CAS was exceptional on the physiology and theory. It was very (very, very) weak on the evidence side. Partly because finding this evidence is so difficult, a task set by the legal system that I don’t think

…the scientific one can actually achieve (it was the same, by the way, when Pistorius challenged them for the right to run in carbon fiber blades - the court said “prove the advantage”, and I mean, how do you do that? And that’s actually easier than the DSD one!).

So the way this plays out is that maybe Mboma wins a medal in the future, the same discussion happens as for Semenya, and then authorities have to decide if they have the appetite to try to add the 200m the list of regulated events. Presumably they still can’t add all events, and

…maybe they need specific evidence in the 200m. In which case, I guess they measure T levels & look for performance associations, but with only one athlete there, I’d be surprised if they find it. Or is winning enough evidence (it helped their case that 2016 800 podium was DSDs)