The Manifestation of Fragmentation in International Law within the Context of Investment Law and Potential Remedies for Fragmentation Through Interpretative Approaches

Year 2025, Volume: 45 Issue: 1, 38 - 63, 12.08.2025

Zeynep Kurtoğlu Yenipınar İbrahim Kaya

https://doi.org/10.26650/ppil.2025.45.1.1576042

Abstract

The consequences of the fragmentation of international law are clearly observable in the domain of international investment law, which is both influenced by and contributes to this fragmentation. The interaction between investment law and other branches of international law, such as human rights and environmental law, has become increasingly essential. This article examines the necessity of integrating and harmonising investment law with other fields of international law with which it interacts most, including human rights, environmental law, and sustainable development. It proposes the effective application of interpretative methods for treaties as a solution to these issues. When provisions are absent in treaties or when there is a need for harmonised interpretation of existing provisions, the interpretation of international treaties plays a significant role in aligning investment law with other areas of international law. Therefore, as potential solutions, this analysis evaluates the principles of systemic harmonisation outlined in Article 31(3)(c) of the Vienna Convention on the Law of Treaties, the evolutionary interpretation that considers changing circumstances, and the effective interpretation in good faith that takes into account the object and purpose of treaties. These interpretative methods are proposed as fundamental tools for addressing fragmentation and aligning the investor-state dispute resolution process with the broader norms of international law.

Keywords

Fragmentation of International Law , Investment Law , Interpretation of Treaties , Environment , Human Rights , Sustainable Development

Uluslararası Hukuktaki Parçalanma Olgusunun Yatırım Hukukunda Tezahürü ve Parçalanmaya Yorum Yolu ile Getirilebilecek Çözümler

Abstract

Uluslararası hukukun parçalanmasının sonuçları, bu parçalanmaya hem katkıda bulunan hem de bu parçalanma tarafından şekillendirilen uluslararası yatırım hukuku alanında açık bir şekilde görülmektedir. Yatırım hukuku ile insan hakları ve çevre hukuku gibi diğer uluslararası hukuk dalları arasındaki etkileşim giderek daha gerekli hale gelmiştir. Bu makale, yatırım hukukunun, en çok etkileşim içinde olduğu insan hakları, çevre hukuku ve sürdürülebilir kalkınma gibi uluslararası hukukun diğer alanları ile bütünleştirilmesi ve uyumlaştırılması ihtiyacını araştırmakta ve bu sorunlara çözüm olarak antlaşmaların yorumlanmasına ilişkin yöntemlerin etkili uygulamasını önermektedir. Yatırım antlaşmalarında hüküm bulunmadığında veya bulunan hükümlerin bütünleştirici yorumlanması gerektiğinde, uluslararası antlaşmaların yorumu meselesi, yatırım hukukunun diğer uluslararası hukuk alanlarıyla uyumunda önemli bir rol oynamaktadır. Bu nedenlerle, makalede çözüm önerileri olarak sunulan, Viyana Antlaşmalar Hukuku Sözleşmesi’nin antlaşmaların yorumunu düzenleyen 31. maddesinin (3). paragrafı (c) bendinde öngörülen sistemik uyumlaştırma ilkesi, değişen koşulları dikkate alan evrimsel yorumlama yöntemi ve antlaşmaların konu ve amacını dikkate alan iyi niyetli bir yorumu öngören etkili yorumlama ilkesi değerlendirilmektedir. Bu yorumlama yöntemleri, bölünmüşlüğü ele almak ve yatırımcı-devlet uyuşmazlık çözüm sürecini daha geniş uluslararası hukuk normları ile uyumlu hale getirmek için temel araçlar olarak önerilmektedir.

Keywords

Uluslararası Hukukta Parçalanma , Yatırım Hukuku , Antlaşmaların Yorumlanması , Çevre , İnsan Hakları , Sürdürülebilir Kalkınma

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