The decision outraged U.S. Olympic and gymnastics officials, and led to a torrent of online abuse against both Chiles and Ana Barbosu, the Romanian athlete who ended up with the bronze.

Jordan Chiles, right, with Simone Biles, left, and Rebeca Andrade after the floor exercise final last week in Paris.Credit…Chang W. Lee/The New York Times

The head of a panel that ruled that the American gymnast Jordan Chiles had to give up her Olympic bronze medal in favor of a Romanian athlete has represented Romania for almost a decade in arbitration cases, documents show.

The three members of a special tribunal convened for the Olympics by the Court of Arbitration for Sport after Romania lodged a complaint ruled that a successful appeal made by Chiles’s coach over the points awarded to her in the floor exercise competition was initiated four seconds late. The Romanian athlete, Ana Barbosu, was awarded the bronze medal as a result of the panel’s decision, and Chiles was dropped to fifth place.

The result left Chiles brokenhearted: It took away her only individual medal at the Games, and means her appearance on the podium — the first all-Black medals stand at a gymnastics event at the Olympics — is now left with an asterisk. Chiles posted four broken heart emojis on a black background on social media on Saturday after the decision was announced, and later said she was stepping away from social media altogether amid a torrent of racial abuse.

The decision to reallocate the medals in the floor exercise outraged U.S. Olympic and gymnastics officials, who have threatened to take their fight to the Swiss courts. The revelation that Hamid G. Gharavi chaired the panel that resolved the dispute in favor of a Romanian athlete despite having a long relationship with Romania’s government is sure to inflame the case further.

Very little is known about the deliberation and how the panel reached its verdict, with the court publishing just a one-page statement confirming the decisions it made. A detailed document outlining the full reasoning behind the outcome will eventually be sent to all the parties involved.

U.S.A. Gymnastics said on Monday it had been notified by the court that under its rules, the decision cannot be reconsidered “even when conclusive new evidence is presented.”

The gymnastics federation said it would continue to pursue “every possible avenue” for an appeal, including before the Swiss Federal Tribunal. That body, the only one that can hear an appeal against a decision by CAS, the sports court, only considers breaches of process and not new evidence related to the case itself.

In 2021, the Swiss court famously requested a new hearing for a doping case involving a top Chinese swimmer, whose lawyers successfully presented evidence that the chair of the tribunal may have had an anti-Chinese bias based on his social media posts.

A woman stands with her right hand and leg raised.
The Romanian athlete Ana Barbosu was awarded the bronze medal as a result of the panel’s decision.Credit…Daniel Berehulak/The New York Times
Under the court’s rules, panel members, including the chair, must complete a conflict of interest form before reviewing each case that lists three possible outcomes.

The first and third are explicit, revealing no conflict or a conflict so significant that they would require their recusing themselves from a case. The second is more nuanced, allowing arbitrators to reveal potential conflicts but giving them a chance to explain why the potential conflict should not prevent them from hearing a case.

Details first published by The International Institute for Conflict Resolution and Prevention, a nonprofit organization, show that Mr. Gharavi, the presiding arbitrator in the hearing and a lawyer based in France, is currently serving as legal counsel to Romania in disputes at the World Bank’s International Centre for the Settlement of Investment Disputes. Mr. Gharavi’s work on behalf of Romania dates back almost a decade.

Under the sports court’s rules, arbitrators are required to complete conflict of interest declarations before every hearing.

“The issue is whether an Olympic arbitrator who currently represents a country on the global stage can decide a case involving a gymnast of that country, in an unbiased manner,” three arbitration experts wrote in an opinion published on the institute for conflict resolution’s website. “Is it realistic to expect such arbitrator can decide against the interests of that country or of that country’s gymnast, who in this case is represented by the Federation of Romanian Gymnasts?”

Mr. Gharavi said he could not comment on anything related to the case and suggested all such inquires be directed to CAS, which is charged with serving as the final arbiter on global sports disputes. The court said in an email that Mr. Gharavi had disclosed his work with Romania in writing and that none of the parties involved in the hearing had objected to his appointment as the panel’s chair.

“In accordance with the guidelines on conflicts of interest issued by the International Bar Association (IBA), CAS has no reason to remove an arbitrator making such disclosure if the parties do not object to his/her appointment,” the court said in its statement.

Katherine Simpson, an international arbitrator and one of the authors of the opinion piece that first disclosed Mr. Gharavi’s work for Romania, said that even if none of the parties objected, his work on behalf of Romania was significant and meant he would automatically have had to recuse himself under the IBA’s so-called red list of non-waivable activities.

“I don’t understand — especially given the visibility of the case — why he was proposed for this case and why he did not refuse the case when it was offered,” said Ms. Simpson, who is not connected to the case.

Mr. Gharavi won a case on behalf of Romania as recently as June, and his biography on his firm’s website lists Romania as a regular client.

The court later issued a separate statement confirming that it could not reopen the case. It said all the parties involved had had what it described as “ample opportunities” to present their arguments and objections. New evidence, if found, could be used to ask the Swiss Federal Tribunal to order the case be reopened and the CAS “would also reopen the case spontaneously if all parties agree.”

Such an outcome, however, is extremely rare.

CAS rulings are almost always the final word in such cases, with the Swiss tribunal typically rejecting most appeals of the rulings. But the Chiles case is likely to bring new scrutiny about how such matters are handled in international sports. Cases are almost always heard behind closed doors, with the full rationales for decisions sometimes limited to just the parties involved in cases, leaving sports fans and athletes unsure about exactly why certain outcomes have been reached.

Tariq Panja is a global sports correspondent, focusing on stories where money, geopolitics and crime intersect with the sports world. More about Tariq Panja