How evidence becomes authoritative in public policy implementation

Policy scientists and public policymakers are continuously struggling with the troublesome relationship between knowledge and policy. On the one hand, policy and policy processes are generally recognized as having a political nature because they prioritize the generation of will rather than knowledge. On the other hand, it is difficult to accept that knowledge is being wasted or used strategically. One of the main challenges for public policymakers is to reconcile the political rationality of policy processes with the scientific rationality of knowledge and research, for instance by intelligent organization of knowledge generation and knowledge use. This article aims to contribute to the debate on this topic by comparing three policy implementation processes in which knowledge played an authoritative role. On the basis of this analysis of these three ‘white ravens,’ lessons are drawn regarding the conditions under which knowledge becomes authoritative in policy implementation practices.