Abstract
Supervisor ostracism represents a pervasive and detrimental workplace stressor, yet existing research has predominantly focused on reactive coping mechanisms, leaving a critical gap regarding how employees can proactively prevent such mistreatment. To address this problem, this study draws on signaling theory as an overarching framework-integrated with social exchange theory as a downstream mechanism-to propose that employees can actively construct a "moral shield" by engaging in green advocacy, a high-cost, self-transcendent behavior that signals intrinsic moral character. We tested our theoretical model using a multi-method design. Study 1, a scenario-based experiment with 146 supervisors, provided causal evidence that green advocacy leads supervisors to objectively grant interpersonal moral credits, which subsequently reduces their behavioral intentions to ostracize. Study 2, a three-wave time-lagged survey of 434 employees, complemented these findings by confirming that green advocacy is associated with employees' perceived moral credits and reduced perceived ostracism in a field setting. Furthermore, we found that this signaling process is contingent upon the receiver's interpretation: the protective effect of green advocacy is amplified when Supervisory Support for the Environment (SSE) is high. This research contributes to the literature by identifying a novel, behavior-based signaling strategy for averting social exclusion and validating the dual nature (granted vs. perceived) of moral credits in hierarchical interactions.