How to conceptualise energy law and policy for an interdisciplinary audience: The case of post-Brexit UK

Interdisciplinary energy research is essential. It advances our understanding of potential transitions from high to low carbon energy systems. However, it is easier to propose than deliver. It requires translation into a simpler language, to aid communication, but not at the expense of the conceptual language that drives our understanding of complex energy systems. We combine legal, political science, and policy studies to show how to balance the need to communicate accessibly and recognise legal and policymaking complexity. We begin with a statement so accepted in legal studies that it has become a truism: the law in the books is not the same as the law in action. The allocation of legal competences is only one influence on policymaking in a complex system. We describe three key ways to conceptualise this relationship between law, policy, and energy systems, focusing on the: (1) 'on paper' legal separation of powers between different governments, (2) interaction between law and policy in practice, including blurry boundaries between formal responsibility and informal influence, and (3) role of law as one of many contributors to policymaking. We use these approaches to explain the implications of Brexit for UK energy policy.