Groupthink Bias in International Adjudication

Abstract One of the most common assumptions about decision-making is that groups usually enhance the quality of the outcomes of deliberative processes. The research on groupthink behaviour challenges this belief by hypothesizing that certain group constellations excessively seek concurrence and thereby increase the probability of faulty decision-making. Since the decision-making process in international adjudication almost always involves group choices, it is crucial to consider the group environment of collegial court decision-making. This article utilizes the General Group Problem Solving model (GGPS) to ascertain how strong the different group conformity antecedents are pronounced in five international courts (the ICJ, the ITLOS, the WTO AB, the ECtHR and the ICC). The results of the GGPS analysis indicate that the WTO AB and the ICC are most likely susceptible to groupthink effects while the other courts are relatively resilient.