Approximately two-thirds of the world’s nations employ some form of lay participation in both criminal and civil proceedings, such as the use of juries, lay judges, jurors, lay magistrates, and members of lay courts, as well as other lay personnel. This paper examines the evolution and practice of lay participation in China and Russia, which were specifically chosen for this study of lay participation in justice since they share a common socialist past that influenced both their justice systems in the 20th century. The study employed a range of comparative legal methods, namely the micro-comparison, synchronous, and diachronic methods. The problem-chronological method was used to investigate the essential features of lay representation in civil and criminal proceedings, which helped determine the place and role of this social practice in the judicial system. The formal legal method was applied to analyze and interpret the legal norms that transformed and modernized the institution of people’s participation in justice. Historically, both China and Russia have adopted various forms of lay participation, from non-professional people’s courts to state courts with lay assessors. In China, the models of people’s participation in justice have evolved in tandem with changes in the legal system. For instance, traditional China preferred to resolve most civil disputes within local communities in accordance with the regional traditions and status-oriented norms of behavior. The People’s Republic of China has adopted the Soviet model of justice featuring people’s assessors. In modern China, the socialist legal tradition coexists with other traditions, giving rise to a hybrid model of people’s assessors characterized by specific Chinese features. In Russia, unlike China, completely non-professional courts existed only for a specific period of the Old Russian state, gradually giving way to state courts with lay participation. The Russian institution of lay participation in justice has a chronodiscrete nature, i.e. it is characterized by periodic changes from the quasi-Schöffen to the Schöffen model, from the Schöffen model to jury trials, and vice versa. However, there were periods in Russian history during which the Schöffen model coexisted with jury trials, mainly in the last quarter of the 19th century and in the 20th century