LAUSANNE – World Aquatics executive director Brent Nowicki has been subpoenaed by the United States government to testify in an investigation into how 23 Chinese swimmers avoided punishment after testing positive for banned drugs weeks ahead of the Tokyo Olympics.

A US House of Representatives committee in May called on the Department of Justice (DOJ) to launch inquiries ahead of the 2024 Paris Olympics into the doping case that has rocked the sport.

The World Anti-Doping Agency (Wada) has come under increasing criticism and pressure to provide answers on how the those swimmers, some of whom went on to win gold medals in Tokyo, escaped punishment.

“World Aquatics can confirm that its executive director, Brent Nowicki, was served with a witness subpoena by the United States government,” World Aquatics said in a statement to Reuters.

“He is working to schedule a meeting with the government, which, in all likelihood, will obviate the need for testimony before a Grand Jury.”

The FBI, in a statement to Reuters on July 5, said it could not confirm or deny any investigation.

Representatives for the US DOJ did not immediately respond to a request for comment.

Wada said it was aware of the investigation, but had not been contacted by law enforcement and again defended its handling of the case.

“Wada reviewed the Chinese swimmer case file diligently, consulted with scientific and legal experts, and ultimately determined that it was in no position to challenge the contamination scenario, such that an appeal was not warranted,” it said in a statement.

“Guided by science and expert consultations, we stand by that good-faith determination in the face of the incomplete and misleading news reports on which this investigation appears to be based.”

An independent investigation of Wada’s handling of the case by Swiss prosecutor Eric Cottier could be published as early as next week.

The New York Times reported in April that the 23 Chinese swimmers tested positive for trimetazidine, a medication that increases blood flow to the heart and is used to treat angina. The swimmers were cleared by a Chinese investigation, which said they were inadvertently exposed to the drug through food contamination at their hotel.