A closer look at the relationship between justice perceptions and union participation.

In this study, a series of nested models was tested to assess the extent to which the relationship between process-related justice and union participation is mediated by perceived union support and union commitment. Members of a steelworkers' local (N = 615) participated in the study. Fit indices most strongly supported a fully mediated model. Unlike previous research, process-related justice was operationalized as 2 distinct variables: procedural and interactional justice. Interactional justice was found to have a substantially stronger relationship with support perceptions than procedural justice. Results also indicated union support accounted for a greater amount of unique variance in union commitment than perceived union instrumentality. The results are discussed in relation to trust theory and the generalization of organization science across different types of organizations.