When does evidence affect policy-making? A comparison across policy sectors

Discussion of the importance of evidence based policy is now a commonplace in many nations, and one that is difficult to argue against (what else would we want policy to be based upon if not on some systematic consideration of... [ view full abstract ]

Discussion of the importance of evidence based policy is now a commonplace in many nations, and one that is difficult to argue against (what else would we want policy to be based upon if not on some systematic consideration of pertinent information?). The ambition of evidence based policy has not necessarily been matched, however, by what happens in practice. As a consequence, much has been written about the degrees of use of evidence in policy-making, and gulfs between those who do research of use for policy-making (evidence producers) and those who make public policy (potential evidence consumers). Hence, actual policy-making runs the gamut from real science-led policy-making (SLP) across various degrees of evidence-informed policy-making (EIP) to non-evidentiary policy-making (NEP).
This paper addresses the question: “What drives the use of science in making public policy in different sectors?” We argue this is related to a number of factors. Literature on the science-policy nexus tends to identify two forces that shape the influence of scientific evidence. One is the degree of information asymmetry between experts and other (formal and informal) policy-making authorities; in turn, asymmetry is affected by the tactics or moves used by experts and other actors to create and maintain it. The second force is venue-shifting, that is, the degree to which the venue or forum in which policy content is deliberated and defined is dominated by experts.
The paper catalogues drivers of each dimension of influence of scientific evidence. Generally, different policy sectors have different policy network structures and our hypothesis is that this is likely to be related to the use of evidence in policy making. In turn, these network structures affect symmetry and venue. Asymmetry can be created and maintained in several ways. Public policy research has shown asymmetry arising from various kinds of certification, creations of unified public fronts (deliberative freezing), or stable coalitions supporting expert bodies’ autonomy (coalitions of esteem). Venue-shifting refers to how deliberations and decision-making are organized. Hence, the influence of scientific evidence should increase with delegation to experts or expert bodies, or with fragmentation or specialization in public policy-making. These drivers make information asymmetries and situate deliberations and decision-making, and in turn, shape how evidence influences public policy.
We examine two policy sectors to demonstrate how our framework can be used to distinguish between the likely results. The two sectors are health and employment. Health policy has a substantial evidence base, generated by medical scientists, who dominate as the experts in the sector, are tightly networked and hold their arguments in private. This should result in policy-making that approaches SLP. In contrast, employment policy has an evidence base that is generated by a more different and fragmented group of actors, who are loosely networked, and hold their arguments in public. This should result in policy-making that approaches NEP.