Abstract
Nudging is a behavioral tool that exploits human biases to reduce the intention-action gap. While debates continue over whether nudging is ethically justified, little attention has been paid to its experimental dimension. Because nudging often requires data about human behavior, its implementation can resemble experimental research—and should therefore adhere to ethical standards such as those outlined in the Belmont Report and broader bioethics literature. Liberal nudgers, whether in the public or private sector, must gather information about individuals’ preferences to avoid paternalistically assuming them. This paper argues that many nudges (1) involve experimental elements and (2) should follow the same ethical principles required for human-subject research. The goal is to develop a practical checklist to guide the ethical design of nudges (and alternatives), depending on the interaction of three variables: the accessibility of individual preferences, the transparency of the nudge, and the transparency of its disclosure. Accessing individual preferences would maximize transparency and ethical legitimacy (e.g., surveying employees about their attitudes toward eating healthier foods, additionally disclosing the proposed nudge and its purpose). If preferences are unknown, ethical justification could involve informed consent at the point of intervention (e.g., signage at a cafeteria entrance). When informed consent is unfeasible, a nudge might still be justified through inherent transparency (e.g., highlighting a healthy option). In rare cases where even that is impossible, ethical responsibility would require subsequent debriefing. This checklist helps practitioners evaluate how ethical their proposed nudges are and what steps to take to make them more ethically defensible.