The aim of this study is to show how the institution of joint cases in the Polish civil trial was shaped in the context of Polish criminal procedure and canon law. A comparative analysis of the state of affairs de lege lata will allow us to determine the nature of the procedure aimed at issuing a judgment in cases that have been combined into one proceeding due to their subject matter and thus answer the question whether there is a cumulative judgment in each of the procedures and how is it understood by the legislator in civil, criminal and canon law? The analysis carried out is an important novelty in research on the issue of the institution of a cumulative judgment, because it allows for comparing the analyzed institution not only within the state law system, but also within the autonomous normative system created by canon law.