Abstract
When witnessing aggression, individuals often empathize more with victims than with aggressors, which may bias their perceptions and interpretations of the transgressions. However, the mechanisms underlying these biases remain poorly understood. Through two experiments, we investigated whether people's decisions to condemn aggressors are influenced by their predisposition to sympathize with the victim and explored how negative sentiments towards the aggressor may influence these decisions. Further, we tested the moderating role of callous-unemotional traits, hypothesizing that moral judgements and decisions to punish may differ among individuals who are less emotionally responsive, as they are less likely to sympathize with victims. Our findings revealed that greater empathy for victims intensified punitive attitudes towards aggressors, primarily mediated by participants' negative evaluations of the aggressor. Notably, such empathic inclinations were less prevalent among individuals with higher levels of callous-unemotional traits, as reflected by their lower concern for victims and greater inclination towards harsh punishments. These results offer insights into how justice-related attitudes may be shaped and potentially biased by individual differences in emotional responsiveness.