Uluslararası Teamül Hukukunun Manevi Unsuru: Opinio Juris

Year 2026, Volume: 11 Issue: 1 , 159 - 185 , 28.03.2026

Selcen Nur Kışla

https://doi.org/10.58733/imhfd.1702157

https://izlik.org/JA74AN89XC

Abstract

Uluslararası teamül hukuku, uluslararası hukukun en eski kaynağıdır. Uluslararası hukukta andlaşmaların sayısındaki kayda değer artışa ve en önemli kaynak olarak kabul edilmesine rağmen önemini halen korumaktadır. Fakat, andlaşmalar gibi yazılı bir kaynak olmaması, birtakım zorlukları da beraberinde getirmektedir. Çünkü uluslararası teamül hukuku, devlet uygulamalarının incelenmesini gerektirdiği için andlaşmaların sahip olduğu açıklığa sahip değildir. O nedenle her şeyden önce ispatlanması gerekir. Fakat bu konu, önemli zorluklar barındırmaktadır. Öncelikle ispat hem maddi hem manevi unsur bağlamında ayrı ayrı değerlendirilmesi gereken bir sorundur. Fakat bu zorluğu daha da pekiştiren şey ise manevi unsur yani, opinio juris’tir. Çünkü, tüzel kişiliğe sahip olan devletlere hukuki inanç atfetmek ve bunu ispat etmek son derece zordur. Uluslararası teamül hukukunun maddi unsuru; devletin faaliyetleri ile alakalı olduğu için neden anıldığı anlaşılabilmektedir. Fakat opinio juris açıklanmaya daha çok muhtaçtır. Hem de uluslararası teamül hukukuna asıl hukuk kuralı vasfını kazandıran unsur opinio juris’tir. Çünkü, teamülün tanımı devlet uygulaması ile sınırlanacak olursa, uluslararası nezaket kuralları gibi kurallardan ayrılması mümkün olmaz. Bazen opinio juris’in ispat şekilleri ile devlet uygulama biçimleri arasında örtüşmeler olabilir. Bu durum, bir unsurun ispatının diğeri için de yeterli görülmesi anlayışına yol açmamalıdır. Aksi halde, teamül hukuku tek bir unsura indirgenmiş olur. Ayrıca, bu yöntem, doğru bir yöntem değildir. Opinio juris’in tespiti bütün deliller ışığında yapılmalı ve devletlerin uygulamada bulunurken hukuk kuralı olarak kabul ettikleri ispatlanmalıdır.

Keywords

uluslararası hukuk , uluslararası hukukun kaynakları , uluslararası teamül hukuku , manevi unsur , opinio juris

The Subjective Element of International Customary Law: Opinio Juris

https://izlik.org/JA74AN89XC

Abstract

International customary law is the oldest source of international law. Despite the significant increase in the number of treaties in international law and their acceptance as the most important source, it still maintains its importance. However, the lack of a written source such as treaties brings with it some difficulties. Because international customary law requires the examination of state practices, it does not have the clarity that treaties have. Therefore, it must first of all be proven. However, this issue contains significant difficulties. First of all, evidence is a problem that needs to be evaluated separately in context of both material and subjective elements. However, what further reinforces this difficulty is the subjective element: opinio juris. Because it is extremely difficult to attribute legal belief to states, which are legal entities, and to prove it. The objective element of international customary law; it is understandable why it is mentioned because it is related to the activities of the state. However, opinio juris needs more explanation. Moreover, the element that gives international customary law the real characteristic of a legal rule is opinio juris. Because, if the definition of custom is limited to state practice, it is not possible to separate it from rules such as international courtesy rules. Sometimes there may be overlaps between the forms of evidence of opinio juris and the forms of state practice. This should not lead to the understanding that evidence for one element is sufficient for the other. Otherwise, international customary law will be transformed into a single element. In addition, this method is not a correct method. The determination of the opinio juris must be made in the light of all the evidence and it must be proven that the states accept the practice as law.

Keywords

international law , sources of international law , international customary law , subjective element , opinio juris

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