Uncertainty in the Rules of Customary International Law
DOI:
https://doi.org/10.65263/7b0nx546Keywords:
International Law – International Custom – International Rule – Uncertainty – International Court of JusticeAbstract
The theoretical challenges of customary international law are essentially the same as those faced by international law as a whole, given that the problems of this legal system are interconnected and intertwined. These issues originate from a single root cause, namely the absence of a comprehensive legal system equipped with the necessary structures to eliminate ambiguity and conflict in international legal rules.
Thus, the problem of uncertainty in legal rules, which pervades international law generally, is also found—more prominently and extensively—in customary international law. This uncertainty is not confined to a specific element of customary rules, but rather extends to their origin, formation, structure, evidence, scope, content, and legal nature.
Accordingly, it can be stated that uncertainty, as a structural issue in international law, manifests in a complex manner within this domain. It is not limited to the identification of the criteria for the existence of legal rules, which represents the initial threshold of the problem common to both domestic and international legal systems. Rather, it extends to determining the methods and standards by which legal rules are established and the mechanisms by which they are modified. However, such complexities do not appear with the same degree in domestic legal systems.
International legal scholarship has recognized this multifaceted problem and has sought to find appropriate solutions. Nevertheless, the divergence of research methodologies adopted in addressing the issue has led to conflicting and inconsistent theoretical approaches, which have failed to achieve the intended goal of establishing a sound intellectual and philosophical foundation for resolving the problem within customary international law. It is certain that the multiplicity of theoretical approaches leads to multiple possible interpretations, and consequently, to uncertainty regarding the existence of customary legal rules, which are supposed to be definitive in their existence and content so as to serve as a basis for determining and complying with international obligations.
Despite these practical and theoretical difficulties that hinder legal certainty in customary international rules, there remains a compelling need for continued scholarly inquiry and for deepening the examination of this complex issue. Such inquiry clarifies jurisprudence theories and facilitates comparison and rapprochement among them, thereby rendering them more accessible and comprehensible this being the aim of the present study.
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