Peer Attachment and Prosocial Behavior: The Mediating Role of Positive Legal Emotion and the Moderating Effect of Social Exclusion

Prosocial behavior supports social cohesion and legal order. Drawing on attachment theory and emotional socialization theory, this study examined whether peer attachment promotes prosocial behavior through positive legal emotion, defined as affective identification with and respect for law, and whether social exclusion moderates this pathway. A cross-sectional survey was conducted with 401 Chinese university students. Measures assessed peer attachment, positive legal emotion, social exclusion, and prosocial behavior. Gender and parental education were included as control variables. Correlational and regression analyses were conducted, followed by conditional process modeling using Hayes’ PROCESS Model 60 with 5000 bootstrap resamples to test mediation, moderation, and moderated mediation effects. Peer attachment significantly and positively predicted prosocial behavior. Positive legal emotion partially mediated the relationship between peer attachment and prosocial behavior. Social exclusion significantly moderated the association between peer attachment and positive legal emotion. The indirect effect of peer attachment on prosocial behavior through positive legal emotion became stronger as social exclusion increased. Moderated mediation analyses further confirmed that the indirect effect intensified at higher levels of social exclusion. Positive legal emotion represents an important psychological mechanism linking peer relationships to prosocial outcomes, while social exclusion functions as a key contextual boundary condition. Interventions that strengthen peer support, enhance legal emotional engagement, and reduce social exclusion may promote prosocial and legal socialization among university students and contribute to broader social integration and stability.