This paper presents a normative analysis of restrictive measures in response to a pandemic emergency. It applies to the context presented by the Corona virus disease 2019 (COVID-19) global outbreak of 2019, as well as to future pandemics. First, a Millian-liberal argument justifies lockdown measures in order to protect liberty under pandemic conditions, consistent with commonly accepted principles of public health ethics. Second, a wider argument contextualizes specific issues that attend acting on the justified lockdown for western liberal democratic states, as modeled on discourse and accounted for by Jürgen Habermas. The authors argue that a range of norms are constructed in societies that, justifiably, need to be curtailed for the pandemic. The state has to take on the unusual role of sole guardian of norms under emergency pandemic conditions. Consistently with both the Millian-liberal justification and elements of Habermasian discourse ethics, they argue that that role can only be justified where it includes strategy for how to return political decisionmaking to the status quo ante. This is because emergency conditions are only justified as a means to protecting prepandemic norms. To this end, the authors propose that an emergency power committee is necessary to guarantee that state action during pandemic is aimed at re-establishing the conditions of legitimacy of government action that ecological factors (a virus) have temporarily curtailed.@en