The role of international law in Article 42(1) of the Washington Convention on the Settlement of Investment Disputes

Focusing on the interpretation of Article 42(1) of the ICSID Convention, this thesis examines the ambiguous role of international law in investment disputes. It explores contrasting scholarly theories regarding the application of international law versus host state law, highlighting the lack of consensus and varying limits established by authors and case law. Utilizing both civil and common law interpretative methods, the paper concludes that the current framework allows tribunals discretion in defining international law's scope. It advocates for greater harmonization of foreign investment rules to enhance clarity.