The circumstances of a public health emergency shape reasoning and decision-making in ways that deviate from routine circumstances, where adherence to established values, principles, and methodologies is expected. Understanding what drives these deviations is critical to assessing their ethical consequences. In this paper we describe four conditions that influence decision-making during PHEs, in particular regarding the deployment and conduct of research on experimental or novel biomedical interventions. These four conditions are politicization, urgency, uncertainty, and fear. We argue that taken together (...) these four conditions create pressure to address the most visible targets of immediate crisis events, driving emphasis on research and development of biomedical interventions. However, this emphasis raises ethical concerns regarding the extent to which attention to and investment in the underlying causes of PHEs, particularly impoverished global public health infrastructure, is diminished as a result. (shrink)