Coworker justice and its interaction effects with supervisor justice

Abstract

Studies on justice effects in organizational settings abound, and yet almost all of them focused on justice from an authority figure - typically the organization or the supervisor. The multifoci justice approach recently draws researchers' attention to possible sources of justice other than the organization and the supervisor, but how these understudied sources influence employees' experience of justice together with the traditional sources is not yet clear. To advance this body of literature, in this thesis I examined the effects of one understudied but important source of justice, coworkers. Particularly, I focused on how coworker justice interacts with supervisor justice to affect three important employee psychological outcomes. The outcomes were chosen based on three major theories on justice effects: organization-based self-esteem (OBSE) based on group engagement model, supervisor trustworthiness based on fairness heuristic theory, and personal uncertainty based on uncertainty management theory. It was hypothesized that when coworker justice is high, supervisor justice has stronger effects on employees' OBSE and perceived supervisor trustworthiness and a weaker effect on employees' personal uncertainty. I further examined how the three employee psychological outcomes mediate the interaction effects of supervisor justice and coworker justice on two employee performance criteria: task performance and organizational citizenship behavior (OCB). Altogether a contingent indirect effect model was proposed about the interaction effects of supervisor justice and coworker justice. Two multi-rater, multilevel, and time-lagged field studies were carried out to test the research model. Results showed that when coworker justice was high, the effects of supervisor justice on OBSE and supervisor trustworthiness were stronger; whereas when coworker justice was low, supervisor justice had a stronger positive effect on personal uncertainty. Moreover, OBSE and several facets of supervisor trustworthiness mediated the interaction effects of supervisor justice and coworker justice on employee performance. The research carries implications for the adopted justice theories and advances the justice literature by highlighting the important role of coworker justice in shaping employees' justice experience in the workplace.