‘Big science’ in the field: experimenting with badgers and bovine TB, 1995–2015

Since wild badgers were first connected with outbreaks of bovine TB (bTB) in UK cattle herds in the early 1970s, the question of whether to cull them to control infections in cattle has been the subject of a protracted public and policy controversy. Following the recommendation of Prof. John Krebs that a "scientifically based experimental trial" be carried out to test the effectiveness of badger culling, the Randomised Badger Culling Trial (RBCT) was commissioned by Government in 1998. One of the largest field experiments ever conducted in the UK, the RBCT sought to recreate the conditions of a randomised controlled trial (RCT) across approximately 3000 km(2) of the South West of England. Despite widespread expectations that the RBCT would provide the necessary evidence to resolve the controversy, its findings have instead been widely contested and reinterpreted, while arguments over badger culling have become increasingly polarised. This paper will investigate the complexities of field experimental knowledge by following the story of the RBCT from this initial proposal, through processes of research design, implementation, analysis, interpretation and reinterpretation of the findings by multiple actors. It asks what kind of experiment the RBCT actually was, and examines how it has contributed to the protracted controversy over whether to cull badgers in order to control bTB in cattle. Finally, it will explore the wider implications of this case for contemporary debates over the contribution that RCTs can make to formulating public policy.