LAUSR

Abstract Tobacco policy in the UK and Japan has diverged markedly. In the 1980s, both countries oversaw regimes with minimal economic and regulatory policies. Now the UK has become one of the most, and Japan one of the least, controlled (advanced industrial) states. These developments are puzzling to public health scholars who give primary explanatory weight to scientific evidence and a vague notion of “political will”, because policy makers possessed the same evidence on the harms of tobacco, and made the same international commitment to comprehensive tobacco control. Instead, we identify the role of a mutually reinforcing dynamic in policy environments, facilitating policy change in the UK but not Japan: policy makers accepted the scientific evidence, framed tobacco as a public health epidemic, placed health departments at the heart of policy, formed networks with public health groups and excluded tobacco companies, and accentuated socio-economic conditions supportive of tobacco control. This dynamic helps explain why the UK became more likely to select each tobacco policy control instrument during a series of “windows of opportunity”. Such analysis, generated by policy theory, is crucial to contemporary science/practitioner debates on the politics of “evidence-based policy making”: the evidence does not speak for itself, and practitioners need to know how to use it effectively in policy environments.