Experimental insight into the fair process effect and its boundary conditions: External attributions may moderate reactions to procedural justice in legal contexts

The perception of being treated fairly during decision-making processes is an important topic in the research literature on law and society. Many studies have indeed found that perceived procedural justice affects people’s reactions, for instance, by increasing their trust in legal authorities and lowering their intentions to protest against these authorities’ decisions. Here, we reveal support for this fair process effect and point to some of its potential boundary conditions. In our experimental study, 239 participants imagined being the defendant during a single-judge criminal court hearing that used either a fair or an unfair procedure. Following the experience of a fair as opposed to an unfair procedure, participants showed more trust in judges and were less inclined to protest against the judicial ruling. Interestingly, the effect of the procedure manipulation on trust in judges was moderated by the extent to which participants attributed their case outcomes to external causes. We found a fair process effect among participants with relatively low external attribution ratings, while this effect attenuated and was not statistically significant among participants whose external attribution ratings were relatively high. These findings point to the possibility that attributional processes can moderate people’s responses to procedural justice in legally relevant contexts