Since 1990 Lithuania has been claiming that what happened there during Soviet occupation is genocide, as per the 1948 Genocide Convention, which embodies universal justice for suppressed nations and other groups. Due to Soviet actions in Lithuania throughout the periods of 1940-1941 and 1944-1990, the country lost almost one fifth of its population. The application of Lithuanian national legal regulations regarding this issue has been recently discussed in the framework of another postwar international legal instrument – the European Convention of Human Rights (1950). The goal of this article is to examine the main debates, which were revealed by the European Court of Human Rights in the cases of Vasiliauskas v. Lithuania (2015) and Drėlingas v. Lithuania (2019), regarding the killings of Lithuanian partisans, including the recognition of the significance of partisans for the Lithuanian nation, the foreseeability of genocide “in part,” as well as the punishment for complicity in killing Lithuanian partisans.