Turkey: Concept Of Evidence In Common Law – Civil Law Systems And Under International Arbitration

Last Updated: 19 October 2015
Article by Tugba Tasci

I.  Burden of Proof

Agreements and regulations on international arbitration appear generally to be silent on burden of proof. The parties may occasionally agree on distribution of the burden of proof in certain disputes during the international arbitration proceedings1. As a matter of fact, the parties are obliged to provide their evidences for proving the matters based on their claims and arguments in furtherance to the efficient judgement of arbitral tribunal. Having taken into consideration the international regulations, it is clear that the parties are obliged to prove the facts supporting their claims and defences. For instance, Article 27 of UNCITRAL Arbitration Rules states that each party shall have the burden of proving the facts relied on in order to support his claim or defence. That said, the reason for disappearance of a general regulation with regard to the burden of proof in international arbitration rules is that the tribunal shall evaluate all the evidences provided by the parties whether they have the burden of proving or not.

It is noteworthy to state that UNCITRAL Model Law does not include any rule relating to the burden of proof and therefore the rule concerning the obligation of proving the facts supporting the claims is accepted as a "Generally accepted principle"2. Besides, the rules in relation to the burden of proof may be connected with the substantial law instead of procedural law. For instance, while the rules regarding the burden of proof are being taken into consideration as a part of procedural law in common law systems, they are accepted as relating to the substantial law in civil law system3.

It is a mere fact that arbitrators generally evaluate by taking into consideration that the standards widely accepted within the closest law system in international arbitration practice. In the meantime, concepts used in order for determining the proof criteria vary due to the differences between the common law and the civil law systems. Despite such difference, absolute proving is not generally required with regard to the burden of proof in international arbitration. Nevertheless, an evidence standard so-called "Balance of probability" is widely accepted as criteria, which is considered between the absolute and approximate proving and provides the possibility for the realization of the claimed facts4.

Having been based on the international law, there does not exist any regulation on the proof instruments due to the party autonomy principle which constitutes the basis of the arbitration proceedings. Accordingly, relevant arrangement shall be made for each case and all evidences which have the characteristics of proof instrument to be found beneficial by the arbitral tribunal shall be accepted appropriately. Nonetheless, certain international rules and regulations include provisions with respect to the proof instruments. For example, Article 34 of the ICSID Arbitration Rules states that the tribunal may, if it deems it necessary at any stage of the proceeding, call upon the parties to produce documents, witnesses and experts; and visit any place connected with the dispute or conduct inquiries there. Most particularly, documents, witnesses and experts are widely accepted as proof instruments in the international arbitration proceeding5.

Having been based on the international arbitration rules, an arbitrator or the arbitral tribunal is usually granted with, as the case may be, the appointment of an expert or possibility for application to the expert opinion. In this respect, the parties of the proceeding may appoint the expert, which is so-called expert-witness, or the arbitral tribunal can decide on the appointment of the experts. While the experts are being appointed by the arbitral tribunal in civil law system, the parties submit their own experts to the arbitral tribunal in common law system.

It is a mere fact that the concept of witness in international arbitration has extensive implementation comparing to the national law systems. Accordingly, each person, even if the parties in accordance with institutional arbitration, who may provide his knowledge about the matter in dispute, may be listened as witnesses6.

II.  Taking of Evidence

One of the general objects of a pre-hearing in international arbitration is to clarify the evidence which the tribunal will need to enable it to make an informed decision rooted in a sure foundation of fact. The parties in international arbitration proceedings may define the procedural law to be implemented to the case or agree on certain ad hoc or administrative arbitration rules by reference. If there do not appear any arrangements on any part of the proceeding in accordance with the procedural law chosen by the parties, the arbitrator shall eligibly fill this blank based on his discretion7.

UNCITRAL Model Law lets the parties to be free to agree on the procedure to be followed by the arbitral tribunal in conducting the proceedings. Additionally, if any party fails to appear at a hearing or to produce documentary evidence, the arbitral tribunal may continue the proceedings and make the award on the evidence before it. The arbitral tribunal may, of course, appoint one or more experts to report to it on specific issues to be determined by the arbitral tribunal. The most significant point is that the arbitral tribunal or a party with the approval of the arbitral tribunal may request from a competent court of this state assistance in taking evidence.

On the other hand, legal arrangements in civil law systems contain certain provisions regarding taking of evidence by providing the possibility of application of state courts. Additionally, experts may be appointed by the arbitrators as well as the parties. The parties have also possibility to ask questions to the experts. Nevertheless, common law systems contain different regulations concerning the taking of evidence. The issues with respect to the evidence are individually determined and the expert may be only appointed by the arbitrators. Of prime importance is the fact that the discovery method, a procedure which carries a meaning of collection of evidence from the third persons who are not the parties of the dispute, is accepted. The arbitrator is allowed to accept a witness before the proceedings and cross-examination method is applicable in common law.

Witnesses, including expert witnesses, who are presented by the parties to testify to the arbitral tribunal on any issue of fact or expertise, may be any individual, notwithstanding that the individual is a party to the arbitration or in any way related to a party. Unless otherwise directed by the arbitral tribunal, statements by witnesses, including expert witnesses, may be presented in writing and signed by them. At any time during the arbitral proceedings the arbitral tribunal may require the parties to produce documents, exhibits or other evidence within such a period of time as the arbitral tribunal shall determine. The arbitral tribunal shall determine the admissibility, relevance, materiality and weight of the evidence offered.

III.  An Analytical Approach: IBA Rules

The international arbitral community is greatly assisted in many of points considered by the IBA Rules on the Taking of Evidence in International Arbitration which have managed to provide a practical balance between traditional civil law and common law ways to deal with the reception of evidence.

The IBA Rules on the Taking of Evidence in International Arbitration are intended to provide an efficient, economical and fair process for the taking of evidence in international arbitrations, particularly those between parties from different legal traditions. They are designed to supplement the legal provisions and the institutional, ad hoc or other rules that apply to the conduct of the arbitration. Since the international regulations do not contain comprehensive arrangements on the taking evidence, these rules are generally used as supplementary rules in international arbitration8. Where the parties have agreed to apply the IBA Rules of Evidence, they shall be deemed to have agreed, in the absence of a contrary indication, to the version as current on the date of such agreement.

The Arbitral Tribunal shall determine the admissibility, relevance, materiality and weight of evidence. According to Article 9 of the IBA Rules, based on the grounds determined within this provision, the arbitrator may refuse the acceptance of evidence. Additionally, the discovery method, as used as a system in common law, is also applicable for the proceedings in accordance with the IBA Rules. On the other hand, aforesaid rules provide to the parties a mutual method for hearing the witness which covers both common law and civil law regulations. New methods for hearing a witness, such as witness conferencing, are also being implemented under IBA Rules. That being said, experts may be appointed by both the parties and the arbitrators.

IV.  Conclusion

Evidence is clearly playing a big role on proving the facts within international arbitration. In light of the above-given considerations, while the parties are determining the rules regarding the proof instruments, indispensable principles required for a fair trial should always be considered by the parties and arbitrator. The evidence should be accepted as necessary unless the principles are used as contrary to the law during the proceedings.

As previously stated, international arbitration rules as well as the international administrative arbitration rules do not contain comprehensive arrangements concerning the evidences. In practice, the differences arisen out of the law systems are being removed by the making an application to the IBA Rules. Types of the evidences, taking, providing and evaluating of evidences should require very detailed regulations in the international dispute resolution systems in order to protect the fundamental principles and provide a fair trial to the parties within the framework of public policy.


1  PIETROWSKI, Robert Pietrowski, "Evidence in International Arbitration" in Arbitration International, V. 22, I. 3, 2006, p. 379.

2  LEW, Julian D. M./MISTELIS, Loukas A./KRÖLL, Stefan, Comparative International Commercial Arbitration, Kluwer Law International, 2003, p. 560.

3  HOLTZMANN, Howard/NEUHAUS Joseph, A Guide to the UNCITRAL Model Law on International Commercial Arbitration, Kluwer International, 1989, p. 568.

4  YEŞİLIRMAK, Doğrudan Görüşme, Arabuluculuk, Hakem-Bilirkişilik ve Tahkim, p. 114.

5  ALANGOYA, Yavuz, "UNCITRAL Tahkim Yönetmeliği Hakkında" Prof. Dr. İlhan E. Postacıoğlu'na Armağan, İstanbul, 1990, p. 20.

6  OETIKER, Christian, "Witnesses Before the International Arbitral Tribunal" in ASA Bulletin, 2007, V. 25, I. 2, p. 254.

7  SANDERS, Pieter, The Work of UNCITRAL on Arbitration and Conciliation, 2. b., The Hague, Kluwer Law International, 2004, p. 103.

8  KAUFMANN-KOHLER, Gabrielle: "Soft Law in International Arbitration: Codification and Normativity" in Journal of International Dispute Settlement, V. 1, No. 2, 2010, p. 289

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