Policy decision-making under scientific uncertainty: radiological risk assessment and the role of expert advisory groups.

Standard-setting agencies such as the U.S. Nuclear Regulatory Commission and the U.S. Environmental Protection Agency depend on advice from external expert advisory groups on matters of public policy and standard-setting. Authoritative bodies including the National Research Council and the National Council on Radiation Protection and Measurements provide analyses and recommendations that enable the technical and scientific soundness in decision-making. In radiological protection the nature of the scientific evidence is such that risk assessment at radiation doses typically encountered in environmental and occupational settings is highly uncertain, and several policy alternatives are scientifically defensible. The link between science and policy is problematic. The fundamental issue is the failure to properly consider risk assessment, risk communication, and risk management and then consolidate them in a process that leads to sound policy. Authoritative bodies should serve as unbiased brokers of policy choices by providing balanced and objective scientific analyses. As long as the policy-decision environment is characterized by high scientific uncertainty and a lack of values consensus, advisory groups should present unbiased evaluations of all scientifically plausible alternatives and recommend selection criteria that decision makers can use in the policy-setting process. To do otherwise (e.g., by serving as single position advocates) weakens decision-making by eliminating options and narrowing discussions of scientific perspectives. Understanding uncertainties and the limitations on available scientific information and conveying such information to policy makers remain key challenges for the technical and policy communities.