국제 재판에서의 과학적 증거의 증명력 - 교차심문 제도를 활용한 국제사법재판소의 과학적 증거 수용 경향 -

The International Court of Justice (ICJ) has progressively refined its approach to the reception and assessment of scientific evidence, reflecting an institutional evolution in its evidentiary procedures. This article examines the Court’s developing case-law on admissibility of scientific evidence through Pulp Mills on the River Uruguay (2010), Whaling in the Antarctic (2014), and Dispute over the Status and Use of the Waters of the Silala (2022)—to shed light on a gradual jurisprudential shift from inadmissibility to weighing of the evidence. In the Pulp Mills Case, the Court’s reluctance to admit scientific evidence underscored procedural deficiencies in the appointment of experts, thereby revealing the significance of due process in the presentation of scientific evidence for the relevant disputes. The Whaling Case judgment marked a doctrinal inflection point: by employing the cross-examination of legitimately appointed experts, the ICJ established a practical mechanism to weigh the probative value of scientific evidence in its proceedings. This evolution was further reflected in the Silala River Case, where the Court reaffirmed and solidified the use of expert cross-examination, signaling its continued transition toward evidence-based judicial reasoning in matters involving scientific uncertainty. Expert cross-examination has thus emerged as the ICJ’s principal procedural tool for assessing the probative value of scientific evidence. Nevertheless, the Court’s scientific fact-finding process remains constrained by its limited in-house scientific capacity and its dependence on party-appointed experts. The persistent challenge lies in maintaining judicial neutrality while expanding the scope of fact-finding to grapple with the indeterminacy inherent in scientific inquiry. As contemporary international disputes increasingly implicate environmental and scientific complexities —particularly in the context of climate change— international adjudicative bodies must strengthen their evidentiary and procedural frameworks. The institutionalization of scientific evidence assessment mechanisms, diversification of evidentiary formats, and expansion of the Court’s capacity by appointing independent experts will be pivotal to enhancing the legitimacy of scientific evidence in international adjudication. This procedural evolution not only reinforces the Court’s fact-finding authority but also delineates an emerging paradigm for integrating scientific expertise into international law.