Background
The principle nemo iudex in causa sua—no one should be a judge in their own cause—has deep roots in international law, yet its codification in the UN Charter has often been disregarded. Article 27(3) requires a State that is a party to a dispute to abstain from voting on related Security Council resolutions under Chapter VI, provided the matter is non-procedural. Although long viewed as dormant, the Russia–Ukraine war has revived interest in this principle.
The last notable compliance with Article 27(3) dates back to the Eichmann case in 1961, when Argentina abstained. Since then, the rule’s relevance has been questioned, particularly amid Russia’s repeated vetoes of Ukraine-related resolutions following its 2014 annexation of Crimea and the 2022 invasion. Given Russia’s clear status as a ‘party to the dispute,’ scholars and practitioners have seen an opportunity to reassert Article 27(3) and to crystallize a workable definition of that term.