This article reviews extant conceptualizations of procedural justice and reports the results of an empirical study testing the effects of fair deliberation. From a communicative action perspective, we argue that Habermas’s conceptions of speech conditions and validity conditions can be used to evaluate the discursive and substantive dimensions of procedural justice in deliberation. That is, fair deliberation is built on the fulfillment of discourse norms and the communicativeness of dialogic interactions. The communicative measures are compatible with extant procedural justice measures and provide a communication-centered ground for evaluating deliberative outcomes related to procedural justice. The case study involves public discussion of the Singaporean government’s population policies on an online deliberative platform. The results show that when procedural justice is presented in the realization of both speech conditions and validity conditions, it fosters participants’ beliefs in the rightfulness of deliberative policymaking. Additionally, speech conditions play a more important role than validity conditions in predicting citizens’ specific policy support after online deliberation. The findings illustrate one instance of how communicative norms are prioritized in different deliberative settings and what deliberative benefits a fair procedure can achieve. The results shed light on the theorization of procedural justice and advance the extant knowledge of evaluating procedural justice in deliberation.