Originally from Take the Witness: Cross-Examination in International Arbitration, 2d Ed.

Cross-examination is quintessentially a concept of common law procedure. It refers to the oral questioning by counsel on behalf of one of the parties of a witness called by another party during a trial or comparable stage of procedure. It is conducted according to rules of practice and procedure distinct from those that apply to the oral questioning of witnesses in other circumstances.

The elements of this definition require some comment. First, cross-examination is part of an oral procedure. A series of written questions put to a witness, if permitted in the applicable procedure, is not cross-examination. Second, cross-examination is always performed by counsel; questioning of a witness by a judge, arbitrator or other judicial or administrative officer is not a cross-examination. Third, it refers to questioning by counsel of a witness called by another party, as counsel is not permitted the same freedom to question a witness that his client has called. Cross-examination presupposes a differential treatment of the questioning of witnesses depending on which party has called the witness. Cross-examination is therefore the complement of the examination of witnesses, which refers to oral questions by counsel on behalf of a party of a witness called by the same party (also called “examination-in-chief” or “direct examination”). Finally, cross-examination occurs in the dispositive stage of the proceedings, and can therefore be distinguished, for example, from a deposition in U.S. civil procedure.

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This chapter will examine the nature and meaning of the common law concept of cross-examination, and its suitability for international arbitration. It will suggest that international arbitration practitioners are best to avoid this term, and should be vigilant to avoid the casual acceptance of the rules that underlie it in common law jurisdictions. Instead they should maintain and defend the existing practice of a neutral and flexible concept of the questioning of witnesses.