Inconsistency in the practice of investment tribunals on issues of proof: does the reform have anything to offer?

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Author: Adam Nal’giev

DOI: 10.21128/2226-2059-2023-3-65-87

Keywords: investment arbitration; investment disputes; reform; inconsistent practice; burden of proof; standards of proof


Reform of the existing system of investment dispute settlement has been on the agenda of the United Nations Commission on International Trade Law (UNCITRAL) for several years now. One of the main problems negatively affecting the legitimacy of the current regime is the inconsistent practice of investment tribunals pertaining to the application of investment treaties. States have suggested different solutions, including institutional reforms such as creating a multilateral investment court or a permanent appellate body, as well as the development and adoption of instruments of authoritative interpretation. However, these options have been discussed exclusively in relation to the practice of investment tribunals regarding the interpretation and application of provisions of investment treaties, while what remains unaddressed is the practice regarding issues that seldom find any embodiment in the text of investment treaties, specifically, issues of burden of proof and standard of proof. In this article, the author discusses the problem of inconsistent practice of investment tribunals regarding burden of proof and standard of proof that had previously been widely covered in academic literature. The author demonstrates that, on various issues pertaining to the allocation of burden of proof or determining the standard of proof applicable to certain factual statements, investment tribunals frequently come to diametrically opposed conclusions which are not predetermined by the applicable law or the circumstances of the particular case. As a result, this practice has a negative influence on the existing system of settlement of investment disputes. The author seeks to evaluate the extent to which the reform options are capable of tackling the problem described, as well as whether proposals of additional directions of reform, namely the adoption of “soft law” instruments on the issues of burden and standards of proof as guiding principles, are capable of doing this.

About the author: Adam Nal’giev – Ph.D. Student, School of International Law, Faculty of Law, Higher School of Economics, Moscow, Russia.

Citation: Nal’giev A. (2023) Neposledovatel’nost’ praktiki investitsionnykh tribunalov po voprosam dokazyva­niya: mozhet li reforma chto-to predlozhit’? [Inconsistency in the practice of investment tribunals on issues of proof: does the reform have anything to offer?]. Mezhdunarodnoe pravosudie, vol. 13, no. 3, pp. 65–87. (In Russian).


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