The Athletics Integrity Unit said on Wednesday it has filed an appeal with the Court of Arbitration for Sport in the case that cleared American sprinter Erriyon Knighton of a doping offence, thus allowing him to compete at the Paris Olympics.
Knighton, 20, tested positive for a banned substance in March but avoided a ban as the US Anti-Doping Agency said an independent arbitrator ruled it was likely caused by contaminated meat and that he was not at fault and had not acted with negligence.
The finding cleared the 200 metres world silver medallist to run at the US Olympic trials in June and he went on to compete in Paris where he finished fourth in the men's 200m final.
The AIU, an independent body created in 2017 by World Athletics to manage integrity issues for the sport of athletics, said it has challenged the first instance decision that Knighton had established no fault or negligence.
"This appeal is against the decision of an arbitration tribunal in the United States that the athlete established no fault or negligence after USADA brought charges against the athlete for the presence of epitrenbolone and use of trenbolone," the AIU said on X.
USADA Chief Executive Travis Tygart said in a statement on Wednesday he understood the AIU's reasons for appealing the case, which he called an example of the system at work, before pointing a finger at the World Anti-Doping Agency.
"The real issue in this case is Wada's bad rule. Trenbolone, the substance in Knighton’s case, is a known livestock enhancer and known to be found in the meat supply," Tygart said.
"We have advocated for the rules around contamination to formally change for years, and Wada has refused to act swiftly."
US and global anti-doping authorities have been at loggerheads since the case involving 23 Chinese swimmers who tested positive for a banned substance before the Tokyo Olympics in 2021 but were allowed to compete.