Since the publication of the seminal book Nudge by Thaler and Sunstein, several critics have highlighted preference endogeneity as a serious obstacle to nudging. When individuals hold preferences that are dynamic and endogenous to the nudge frame, it is unclear what the normative benchmark for libertarian paternalistic policies should be. While acknowledging this issue, the pro-nudging camp has not yet sufficiently addressed it. This article aims to fill this void by presenting a conditional defence of nudging when preferences are endogenous. We explain the learning process through which individuals establish ‘agentic’ preferences: preferences that are sufficiently stable, reasonable, autonomous and associated with organismic well-being to ground the ‘welfare’ principle of libertarian paternalism. To describe this process, we draw on theories from psychological science, in particular self-discrepancy theory and self-determination theory. We argue that agentic preferences are not only welfare-relevant and thus appropriate to libertarian paternalism but can also be identified by choice architects.

Anti-crime policy is often unresponsive to reductions in crime. To address why, we provide a model and empirical test of how citizens’ anti-crime policy preferences respond to information. Our model shows that preferences for anti-crime policy hinge on expectations about the crime rate: punitive policies are preferred in high crime contexts, whereas social policies are preferred in low crime contexts. We evaluate these expectations through an information experiment embedded in the 2017 Latin American Public Opinion Project survey conducted in Panama. As expected by our theory, a high crime message induced stronger preferences in favour of punitive policies. Unanticipated by our theory, but in line with cursory evidence and survey results, we find that a low crime message did not induce stronger preferences in favour of social policies. These findings are consistent with policy ratcheting: punitive policies increase during periods of high crime and remain in place during periods of low crime.