The populist political strategy has become a worldwide phenomenon among those in the executive and legislative branches of government. It is therefore justified to scrutinize whether populism influences the third branch of power, and if so, how. In the first instance, this research project will explore the characteristics of populist judicial reasoning in order to identify populist judgements. The results can be used to determine the extent to which populist judicial practice is widespread in a given legal system. First, I distinguish between three types of populist judicial behaviour. Judicial populism can manifest in the content of the decision (‘decisional’), in the court's communication (‘rhetorical’), or in both (‘full-fledged’). I then present the patterns of reasoning that can indicate populist judicial behaviour in each manifestation of judicial populism. Finally, I will address the question of how a variant of judicial formalism, which I term ‘justificatory formalism’, contributes to the spread of ‘decisional’ judicial populism.