I. INTRODUCTION Prosecutors wield tremendous power, which is kept in check by a set of unique ethical obligations. (2) They must prosecute offenders and do so with vigor. At the same time, they must serve as ministers of justice charged with considering the interests of the very defendants they prosecute. (3) In this Article, I argue that these “dual roles” (4) place demands on prosecutors that are untenable from a psychological perspective. Specifically, I apply the lessons of cognitive science to offer a comprehensive approach to identifying the ways in which prosecutors’ distinctive institutional environment may undermine not just their willingness to play fair but also their ability to do so. This approach bridges prevailing schools of thought about the misuse of prosecutorial power, allowing for more nuanced predictions as to when prosecutors are most likely to transgress.