Art. R34: Challenge
An arbitrator may be challenged if the circumstances give rise to legitimate doubts over her/his independence or over her/his impartiality. The challenge shall be brought within seven days after the ground for the challenge has become known.
Challenges shall be determined by the Challenge Commission, which has the discretion to refer a case to ICAS. The challenge of an arbitrator shall be lodged by the party raising it, in the form of a petition setting forth the facts giving rise to the challenge, which shall be sent to the CAS Court Office or the CAS Anti-Doping Division Court Office. The Challenge Commission or ICAS shall rule on the challenge after the other party (or parties), the challenged arbitrator and the other arbitrators, if any, have been invited to submit written comments. Such comments shall be communicated by the CAS Court Office or the CAS Anti-Doping Division Court Office to the parties and to the other arbitrators, if any. The Challenge Commission or ICAS shall give brief reasons for its decision and may decide to publish it.