In a recent decision,(1) the Supreme Court dismissed Chinese Olympic swimmer Sun Yang's challenge against the final award issued by a newly constituted panel of the Court of Arbitration for Sport (CAS), thereby upholding that panel's (and the former panel's) finding that Yang had violated anti-doping rules and banning him for a period of four years and three months.


In September 2018, Yang eluded anti-doping control by refusing to release his samples to the testing officers, as he considered that they had not shown the necessary certifications for testing. In January 2019, the Anti-Doping Commission of the International Swimming Federation cleared the swimmer of any violation of anti-doping rules. In February 2019, the World Anti-Doping Agency (WADA) appealed the Commission's decision before the CAS. In February 2020, a CAS panel found that Yang had violated the International Swimming Federation's Doping Control Rules and suspended him from competitions for a period of eight years.

In June 2020, Yang filed a request for review of the CAS award before the Supreme Court, seeking the annulment of the award and the disqualification of the presiding arbitrator based on comments made by the latter on Twitter in 2018 and 2019, which allegedly showed racial prejudice against Chinese nationals. In December 2020, the Court granted Yang's request and annulled the CAS award, finding that those comments gave raise to justifiable doubts as to the arbitrator's impartiality and thus that the panel had not been properly constituted.(2)

In February 2021, a new CAS panel was constituted to rehear the case. In June 2021, the new panel issued its award. Yang challenged this award before the Court, invoking the CAS's lack of jurisdiction as well as a violation of his right to be heard and of public policy.


First plea
In his first plea, the plaintiff argued that the WADA's appeal to the CAS was lodged belatedly and thus that the CAS panel had wrongly accepted jurisdiction. The Court found that the plea was inadmissible, confirming its recently established practice whereby the failure to observe a time period to appeal does not entail the arbitral tribunal's lack of jurisdiction but only the inadmissibility of the appeal.(3) According to the Court, even if he had alleged to have been brought before the CAS in an irregular manner, the plaintiff had suffered no denial of justice, as he:

was nevertheless given the opportunity to put forward all his arguments . . . before a genuinely independent and impartial tribunal, the CAS, a specialised court with full power of review in fact and in law, and . . . he was then given the opportunity to bring a legal action before the Supreme Court, whose particular procedural rules, and in particular the extremely limited grounds for appeal, are compatible with the guarantees of the ECHR.(4)

The plaintiff also argued that, further to the WADA's belated appeal to the CAS, the Commission's decision had res judicata effect, which the CAS panel had failed to observe in violation of procedural public policy. According to the Court, it was doubtful that the plaintiff could invoke the res judicata effect of a first-instance decision in order to refuse to follow an allegedly belated appeal lodged by the other party. The concept of res judicata:

presupposes the existence in time of two distinct trials, with a second lis pendens, which would exclude its implementation in the relationship between two courts of different degrees (first and second instance) dealing with the same case.(5)

In any event, the Court found that the WADA's appeal was not belated.(6)

Second plea
In his second plea, the plaintiff raised a series of violations of his right to be heard. In this respect, the Court recalled that there is no general principle in international arbitration requiring that all procedural steps should be repeated when an arbitrator has been challenged and replaced. In the present case, the CAS panel had allowed the parties to present (once again) their arguments on the admissibility and the merits of the appeal, and it had also held a hearing, thereby making every effort to respect the parties' right to be heard.(7) Furthermore, having failed to complain about the page limitation of the pleadings in the arbitration proceedings, the plaintiff was forfeited from doing so in the challenge proceedings based on the rules of good faith. In any event, such limitation did not affect the plaintiff's right to be heard in the circumstances, as he had been provided an opportunity to put forward all his arguments on this issue and he had not established how the outcome of the case might have been different if the alleged violation of his right to be heard had not occurred.(8)

The Court also rejected the plaintiff's appellatory criticism as to the formalities of the anti-doping test and his reasoning based on the burden of proof, which is not subject to the Court's review. Furthermore, the Court found that the CAS panel had not ignored the plaintiff's evidence on the issue of a testing officer's professional credentials but merely found that his argument on that issue was not sufficiently established. Under the guise of an alleged violation of his right to be heard, the plaintiff was in fact challenging the arbitrators' assessment of evidence, which is beyond the review of the Court. Further, the Court found that the new CAS panel was not required to carry out any further investigations or to allow the production of new evidence. Therefore, the plaintiff had only himself to blame for failing to produce, in a timely manner, all the evidence in support of his arguments.(9)

Similarly, the Court found that the CAS panel's refusal to accept the plaintiff's position on a number of issues did not mean that it ignored such position.(10)

Third plea
In his third plea, the plaintiff contended that the disputed award was contrary to substantive public policy, as it violated several fundamental rights and thus his personality rights. The Court recalled that, depending on the circumstances, the infringement of an athlete's personality rights may be contrary to substantive public policy. However, the violation of article 27(2) of the Swiss Civil Code (which prohibits excessive restrictions to the personal freedom) is not automatically contrary to substantive public policy; there must be a serious and clear violation of a fundamental right.(11) Furthermore, the automatic application of criminal law principles and the corresponding guarantees contained in the European Convention on Human Rights (ECHR) is not self-evident in the case of disciplinary penalties imposed by private law associations such as sports federations. In this respect, the Court referred to a decision of the European Court of Human Rights, which confirms that the pursuit of fair sport is an important objective that can justify serious infringements of an athlete's rights.(12)

The only issue to be solved by the Court was whether the result reached by the CAS panel rendered the disputed award incompatible with substantive public policy. Contrary to the plaintiff's position, the issue was not to determine, in the abstract, whether any athlete is obliged, and if so under what conditions, to submit to an unannounced doping test whatever the circumstances. The Court found that the formalities of the anti-doping test were consistent with the applicable rules and that the plaintiff was in fact seeking to challenge the CAS panel's interpretation of such rules, which is not subject to review by the Court.(13)

Finally, the Court declared inadmissible the plaintiff's argument that the Court's limited power of review is incompatible with article 13 of the ECHR (ie, right to an effective remedy). The provisions of the ECHR are not directly applicable in challenge proceedings against arbitral awards, and the plaintiff did not link his criticisms to any of the pleas listed exhaustively in article 190(2) of the Private International Law Act. Furthermore, referring to a decision of principle,(14) the Court carried out a detailed analysis of the compatibility of the specific rules governing challenge proceedings before the Court with the ECHR guarantees, and it came to the conclusion that they are compatible.(15)


This decision puts an end to a case that has been ongoing for three years and has resulted in the issuance of six decisions by the Supreme Court. It is the umpteenth confirmation of the Court's limited power of review in challenge proceedings against arbitral awards. In particular, the Court does not review the arbitral tribunal's assessment of evidence and its interpretation of the applicable rules.

For further information on this topic please contact Frank Spoorenberg or Daniela Franchini at Tavernier Tschanz by telephone (+41 22 704 3700) or email ([email protected] or [email protected]). The Tavernier Tschanz website can be accessed at www.taverniertschanz.com.


(1) Supreme Court, 4A_406/2021, 14 February 2022.

(2) For further information, see "Investigating arbitrator bias: extensive screening of social media not necessarily expected".

(3) Ground 4.1, referring to Supreme Court, 4A_413/2019, 28 October 2019, ground 3.3.2 and other subsequent decisions.

(4) Ground 4.2.

(5) Ground 5.

(6) Grounds 4.3 and 5.

(7) Ground 6.2.2.

(8) Ground 6.2.2.

(9) Ground 6.3.2.

(10) Grounds 6.4 and 6.5.2.

(11) Ground 7.3.

(12) Ground 7.5.

(13) Ground 7.6.

(14) Supreme Court, 4A_248/2019, 25 August 2020.

(15) Ground 8.