Drawing on the social-psychological theory about justice, the current study uses survey data collected during a public engagement process related to nuclear energy to test the relative impact of perceptions about the fairness of outcomes, decision procedures, and interpersonal treatment in predicting both perceived favorability of a decision and willingness to accept a decision. Media use, interpersonal discussion, competence, and risk perceptions (worry) are used as control variables alongside standard demographics in hierarchical ordinary least squares regression models. The study finds that believing one receives a fair outcome is associated with decision favorability, while all forms of fairness perceptions are associated with acceptance. The implication is that perceptions about both outcome and nonoutcome forms of fairness are important to consider when assessing public engagement.