Merely opting out of a public good is moralized: an error management approach to cooperation.
People regularly free ride on collective benefits, consuming them without contributing to their creation. In response, free riders are often moralized, becoming targets of negative moral judgments, anger, ostracism, or punishment. Moralization can change free riders' behavior (e.g., encouraging them to contribute or discouraging them from taking future benefits) or it can motivate others, including moralizers, to avoid or exclude free riders; these effects of moralization are critical to sustaining human cooperation. Based on theories of error management and fundamental social domains from evolutionary psychology, we propose that the decision to moralize is a cue-driven process. One cue investigated in past work is observing a person illicitly consume collective benefits. Here, we test whether the mind uses a 2nd cue: merely opting out of contributing. Use of this cue creates a phenomenon of preventive moralization: moralization of people who have not yet exploited collective benefits but who might-or might not--in the future. We tested for preventive moralization across 9 studies using implicit and explicit measures of moralization, a behavioral measure of costly punishment, mediation analyses of the underlying processes, and a nationally representative sample of almost 1,000 U.S. adults. Results revealed that merely opting out of contributing to the creation of exploitable collective benefits--despite not actually exploiting collective benefits-elicited moralization. Results further showed that preventive moralization is not due to the moralization of selfishness or deviance but instead follows from the uncertainty inherent in moralization decisions. These results imply that even people who will never exploit collective benefits can nonetheless be targets of moralization. We discuss implications for social and political dynamics.