Procedural justice is known to enhance perceptions of police legitimacy. Studies show that procedural justice may be less effective for some individuals and groups, while others show it to be more effective. This study investigates the contingency of the procedural justice effect and considers the effectiveness of procedural justice for certain individuals through the concept of disengagement. Utilizing a survey of 1480 ethnic minority group members, the study tests whether or not disengagement moderates the effect of procedural justice on perceptions of police legitimacy. As expected, we find procedural justice is linked to enhanced perceptions of police legitimacy, while disengagement is associated with reduced perceptions of legitimacy. Interestingly, the study finds that procedural justice is more effective for building legitimacy for ethnic minority respondents who report being highly disengaged from police. These findings highlight how police might be able to improve perceptions of their legitimacy among disaffected minority communities.