Arbitration cases may revolve around complex facts. It is then of utmost importance to shed light on them, so that arbitrators have a better understanding of the case. Tribunals will often hear the witness evidence of individuals who were directly involved in the facts of the dispute, especially where these facts are still controversial.

In international arbitration, parties usually present witness statements along with their written submission, before the hearing is held. These witness statements describe what the witness will testify to. Presenting witness statements yields three different results:

  • The party presenting the witness discloses what the witness knows and has to say about the facts;
  • The opposing party is able to prepare for efficient (cross-)examination of the witness;
  • The arbitrator may detect what is relevant about the witness evidence from an early point on.

Once the witness is examined in the hearing, his or her testimony will take precedence over the witness statements previously submitted. Consequently, the evidence presented by witnesses in arbitration hearings may be vital to the outcome of the arbitration.