The law is recognized as a powerful tool to address some of the structural determinants of chronic disease, including ‘obesogenic’ environments which are a major factor in the increasing prevalence of obesity worldwide. However, it is often local – as opposed to national – government that has responsibility for an environment, including the built environment, and their role in reducing obesity using law remains relatively unexplored. With the English government shifting emphasis for improvement of public health from central to local government, this paper reviews the potential for regulatory action by local government to reduce obesity. We took a novel approach to assess the evidence and to identify legal options for implementation by local government: conducting reviews of literature, media reports and case law. Our results provide a clear rational for regulatory intervention that encourages a real choice of behaviour. They highlight strategic legal areas for reduction of obesity through restriction of traffic and promotion of active travel, promotion of access to healthy food and construction of a sustainable and active environment. Importantly, we identify current legal mechanisms for adoption by UK local government including the use of planning, licensing and transport legislation to develop local obesity prevention policy.