Decades of empirical research have shaped our understanding of organizational justice in the workplace and public assessments of police procedures on the street, but only recently has a nascent wave of research sought to better understand the role that officer perceptions of supervisory procedural justice play in shaping their (un)fair interactions with the public. The nascent research testing this relationship has focused on the evidence that officer perceptions of trust in the public is a pathway between internal procedural justice and external procedural justice. This article tests the role of trust and a parallel pathway that incorporates the concepts of work engagement and personal initiative in the procedural justice literature. Relying on a survey of 638 Croatian police officers, this study finds that the effect of supervisory procedural justice on officers’ external procedural justice is positive but indirect through a measure of trust in the public and the proposed engagement/initiative mechanism. The implications of these findings for research and police practice are discussed.