Governing Scientific Uncertainty: Public Certainty Regimes and Democratic Decision-Making

Democratic governments must often make binding decisions while policy-relevant science remains unsettled. This article develops the Public Certainty Regime (PCR) to analyze how institutions make scientific uncertainty administratively usable. It distinguishes two constitutive stabilization mechanisms—evidentiary stabilization and advisory synthesis—from a contingent closure pathway involving epistemic closure and recipient positioning. Comparative historical analysis examines the United Kingdom’s BSE crisis and South Korea’s humidifier-disinfectant disaster. In both, stabilized positions became difficult to reopen as uncertainty narrowed in authoritative outputs and competing claims lacked recognized standing before positions were fixed. The UK Independent Expert Group on Mobile Phones in 2000 serves as an auxiliary within-country temporal contrast: precautionary action proceeded while uncertainty remained visible and external claims entered before the advisory position was settled. The comparison highlights a shift from prospective assessment to retrospective questions of harm and responsibility, alongside three candidate conditions: revision costs, recognized external epistemic standing, and preservation of visible uncertainty. The PCR framework thus distinguishes the institutional work required for action from the additional processes through which usable knowledge becomes publicly settled certainty.