Caster Semenya is Objectively One of the World’s Best Female Runners. Not Everyone Agrees.

Caster Semenya is the fastest female 800 meter runner in the world this year. Now, as she prepares to take her first steps towards win her first Olympic gold in Rio de Janeiro tonight, the 25-year-old South African is being brought back into a familiar—and unwelcome—spotlight.

Semenya, who will compete in the 800 meter run in Rio, has hyperandrogenism, a condition that causes a person to produce excess testosterone. Because of this, Semenya has spent her career—and her very status as a woman—being subjected to public scrutiny.

The runner burst onto the scene in 2009 when she ran 1:55.45 to win gold in the 800 meters at IAAF World Championships in Berlin. Semenya won by more than two seconds, an eternity for the two lap event.

Shortly thereafter, Australian newspaper The Daily Telegraph revealed that the IAAF had subjected her to gender testing. According to the leaked results published in the story, Semenya had triple the amount of testosterone that a “normal” female would have. The IAAF cleared Semenya for competition in July 2010.

Semenya followed up her win in Berlin with a silver medal in the 800 meters at the 2011 IAAF World Championships in Daegu. The next year, she took silver in the event at the 2012 London Olympics. Both of those performances came after the IAAF passed rules requiring female athletes with hyperandrogenism demonstrate that their testosterone levels fall below the male range in order to compete against females.

Testosterone levels are measured in nanomoles per liter (nmol/L). According to the IAAF regulations, the “normal” testosterone levels for male athletes are anything above 10.5 nmol/L, while the normal range for females is between 0.1 nmol/L and 2.8 nmol/L.

“It is not entirely clear how the IAAF established a ‘normal’ range of testosterone for their regulations, especially since there is very little research on testosterone in women outside of clinical populations,” wrote Sari van Anders, an Associate Professor of Psychology, Women’s Studies, Neuroscience and Reproductive Sciences at the University of Michigan, in an email exchange with Paste. “From what I can tell, there were many subjective nonscientific decisions about whom to include and exclude when deciding on ‘norms.’ Interestingly, any citations about where this decision came from were from review papers, not empirical data papers, which means someone’s opinion got cited somewhere, which got cited somewhere, etc. So, even the scientific basis for the norms is based on someone’s subjective decision rather than objective empirical data.”

According to van Anders, the regulations that the IAAF put in place were unfair to female athletes with naturally higher testosterone levels.

“I am shocked by regulations being passed with literally no scientific or evidentiary basis; it may seem like ‘common sense’ that high testosterone equates to maleness and superior athletic performance but there are reasons we use science and not common sense to determine some kinds of truth,” van Anders wrote. “There is literally no scientific evidence linking athletes’ sporting outcomes with their testosterone levels, despite decades of relevant data. And, even the most basic behavioral neuroendocrinology textbook helps Hormone 101 students understand that sex and gender have a number of influences, of which hormones may or may not be one.”

“One more reason, out of many, that the regulations were unfair: though the IAAF says that their hyperandrogenicity regulations are not a form of sex testing, that smacks of a legalese that is simply untrue and illogical. The regulations are only applied to women (i.e., only women are barred from competing if they have higher than gender-specific androgen levels) and clearly high androgens are being used as a de facto test of womanhood; a new genital parade by hormone assay, if you will,” van Anders added in her email.

The IAAF regulations, which required Semenya and athletes like her to lower their testosterone levels in order to compete, took their toll on her career. At the 2015 IAAF World Championships in Beijing, the South African failed to qualify for the 800 meter finals after running 2:03.18 in the semifinals.

The IAAF’s regulations were tested in 2015 when Dutee Chand, a female Indian athlete who also has hyperandrogenism, took the IAAF to court over her right to compete as a female. The Court of Arbitration for Sport ruled in Chand’s favor, writing the following in its conclusion:

The IAAF has not provided sufficient scientific evidence about the quantitative relationship between enhanced testosterone levels and improved athletic performance in hyperandrogenic athletes. In the absence of such evidence, the Panel is unable to conclude that hyperandrogenic female athletes may enjoy such a significant performance advantage that it is necessary to exclude them form competing in the female category.”

Katrina Karkazis is a senior research fellow at Stanford University’s Center for Biomedical Ethics who was an expert witness in the Chand case (Sari van Anders was also an expert witness in the case). Karkazis said that the IAAF’s policy was flawed because, among other reasons, it blended two separate issues together.

“What the policies do really quickly is flip from a problem of categories (where do certain people fall, why should we not have certain women in the women’s category) to questions of unfair advantage,” Karkazis said. “So they’re really two separate issues that have gotten muddled together.”

The Chand case resulted in the IAAF suspending its rules for female hyperandrogenistic athletes. As a result, Semenya was allowed to resume competing with her natural testosterone levels. Now she’s back on top.

In April, Semenya won three national titles in about four hours at the South African Championships. Her winning times in the 400 meters and 800 meters were both Olympic qualifiers, and her time in the 1500 meters was just outside the mark.

She set a new personal best in the 800 meters on July 15, running 1:55.33 to win at the Meeting Herculis in Monaco and set the Diamond League record. That race came after she won the 800 meter, 1500 meter and 4×400 meter relay titles at the African Athletics Championships. Semenya has three of the five fastest 800 meter times in the world this year. She is dominant.

Semenya is expected to run away with gold in Rio. Karkazis worries that the policy debate over hyperandrogenism will overshadow Semenya’s accomplishments on the track.

“I want her, however well she does, to be able to celebrate her achievements without scrutiny,” Karkazis said. “She deserves that, because she has worked just as hard as anyone else, with incredible dedication, since the last Olympics to be where she’s at right now. If people want to continue to debate the policy, and they will because it’s going back to CAS, she need not be part of that debate. Anyone that understands evidence knows that a sample of one proves nothing. So this is not a debate about her and she should be left out of it.”

Some of the women that Semenya will compete against at the Olympics have made their opinions known on what they see to be an unfair race.

“I think it challenges and threatens the integrity of women’s sports to have intersex athletes competing against genetic women,” said Shannon Rowbury following the first round of the 1500 meters at this year’s U.S. Olympic Trials. “I think Caster is a wonderful person, I have nothing against her. But I think we already have an established precedent of men’s sports and women’s sports and I think we need to honor that.”

Brenda Martinez, who will represent the United States in Rio as a 1500 meter runner, said that she is open to Semenya competing, but that she would like to see the IAAF regulations for testosterone levels reinstated.

“I personally think she should compete. I like Caster, she’s been so nice to me,” Martinez said after the first round of the 800 meters at the U.S. Olympic Trials. “I don’t think anyone should be denied. It’s just not fair, that’s not what our sports about. Yeah she’s different but that’s not her fault. I like her, I respect her, I do want to race her.”

Karkazis said she thinks that Semenya’s competitors might feel that this situation is unfair because of how the IAAF has handled it.

“I think if there hadn’t been the investigation and drama from 2009, that it’s possible that people wouldn’t see it as unfair,” Karkazis said. “In other words they are taking what they think they understand about her body, and what they think they understand about testosterone and athleticism, and looking at her and assuming that her current performance is all due to that.”

Karkazis also added that because Semenya does not fit the assumed idea of feminine for many people, it is easier for people to doubt her.

“But I think there is something more sinister going on here too,” Karkazis said. “Caster Semenya does not present in ways that are stereotypically feminine under the gaze of many people looking. And I think they move very quickly from her gender presentation to making a lot of assumptions about her physiology.”

Semenya is not without her supporters, though. Eleni Schirmer, a doctoral student at the University of Wisconson-Madison, published an open letter to the South African on ESPNW on July 1.

“I will be rooting for you because you are creating a legacy for all humans with bodies. You push us to examine the categories we think we belong to, the ones we have come to believe structure the world,” Schirmer writes in the letter to Semenya.

Both Karkazis and van Anders also made it clear that they think this debate should be about a larger issue, and that the singular focus on Semenya is unfair.

“One of the tragedies of all of this is that what should be a debate about a policy has been narrowed down to a debate about an individual,” Karkazis said.

For van Anders, the media’s focus on Semenya is unethical.

“The media presents a public face of this debate, and I would like to see the IAAF presented as the public face,” van Anders wrote in an email. “It seems unethical for publications to continue the questioning and singling out of an individual athlete’s sex or gender for profit or sensation.”

Michael Sol Warren is a Boston-based freelance writer. Follow him on Twitter @MSolDub.