Some public health behavioral intervention research studies involve deception. A methodological imperative to minimize bias can be in conflict with the ethical principle of informed consent. As a case study, we examine the specific forms of deception used in three online randomized controlled trials evaluating brief alcohol interventions. We elaborate our own decision making about the use of deception in these trials, and present our ongoing findings and uncertainties. We discuss the value of the approach of pragmatism for examining these kinds of ethical issues that can arise in research on public health interventions.