Swiss Arbitration: The scope of the reasonable duty to investigate when assessing the bias of an arbitrator

by Yvonne van der Stroom, LLM, Pachmann Attorneys, Zurich, Switzerland

A recent decision of the Swiss Federal Supreme Court on the legal requirements for establishing possible bias of an arbitrator in arbitration proceedings under the Swiss Private Arbitration Act has important implications for legally challenging the independence of an arbitrator in Court of Arbitration for Sport cases, which can prove problematic in practice.

In its judgment of 22 December 2020, the Federal Supreme Court ruled on the extent to which enquiries must be made regarding the assessment of an arbitrator’s bias. A party may not be satisfied with the arbitrator’s declaration of independence but must make certain enquiries in this regard.

The exact requirements for the duty to investigate depend on the specific circumstances of the individual case. However, the duty to investigate is not unlimited.

Parties can be expected to use the main search engines on the internet and consult certain sources that may indicate a possible risk of bias on the part of the arbitrator.

For example, the websites of the main arbitration institutions, the parties, their legal representatives and the websites of Wada and the sports institutions concerned should be looked at. In addition, the leading social media should be searched.

On the other hand, the parties have no obligation to conduct a systematic and in-depth analysis of all sources relating to an arbitrator.

The fact that information is publicly available on the internet does not automatically mean that the party has not fulfilled its duty to investigate if, despite investigations, it does not come across the specific information.

From a timing point of view, a party cannot be held responsible for information that was published months before the appointment of the arbitrator. For sources published after the appointment of the arbitrator, the party may not be reproached, depending on where and in what quantity information is published.


According to the Federal Supreme Court, a party cannot be expected to make inquiries regarding bias throughout the entire proceedings.


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This entry was posted on 12 Mar 2021 15:45, in Free.