Social Choice and the Risks of Intervention

In this chapter we shall describe and illustrate a framework for assessing risk in the context of social intervention, where by a social intervention we mean a set of actions undertaken, typically by an organized ensemble of agents external to a given society, in order to solve a problem identified within that society. We focus on the general problem of amalgamating expert risk assessment and lay risk assessment. A methodology for integrating divergent assessments of risk has at least two virtues: (1) Where these are presumed to differ, this methodology forces the normative and descriptive assumptions underlying the assessments into the open, so that they can be examined; and (2) It provides risk policymakers with a tool for systematically prioritizing the normative constraints underlying the assessments of risk. We argue that there is no need either to rationalize or to condemn the systematic gap in risk analyses that exists between experts and laypersons. Rather, experts and laypersons should be understood as having different competencies, capabilities and normative requirements. Public (and private) risk managers need a systematic approach to managing these distinctive capabilities and requirements—an approach that recognizes the strengths and constraints of each analytical group, and which allows risk managers to integrate all of these factors. In this paper, we are interested in identifying and analyzing how technical experts’ risk analyses interact with the lay public’s assessments of risk with the principal goal being first to specify formal representations or models of the divergent assessments of risk generated by experts and the lay public and second, to introduce a model for integrating those assessments. We then apply the model to case studies involving natural disasters and health.