Morality and cooperative behavior after adverse experiences in the prisoner’s dilemma game

This study examined how moral reasoning, moral competence, and moral disengagement relate to cooperative behavior in a Prisoner’s Dilemma Game (PDG) in which counterparts followed an adverse pattern of defections. A total of 163 Mexican university students responded standardized moral questionnaires (Defining Issues Test, Moral Competence Test, and Mechanisms of Moral Disengagement Scale) and participated online in a seven-round PDG in which pre-programmed counterparts initially cooperated and later defected. Furthermore, payoff framing (only gains vs. gains and losses) and information about others were experimentally manipulated. Results show a marked decline in cooperation once defections were introduced, which became stronger under possible loss framing, while initial cooperation was higher under greater uncertainty about others’ cooperativeness. More sophisticated moral reasoning predicted continued cooperation despite these adverse conditions. Moral competence and moral disengagement showed no meaningful effects. These findings refine earlier research on “sucker-resistance” in morally sophisticated individuals.