Policy diffusion is an important element of the policy formation process. However, understanding of the micro-level interactions governing policy spread remains limited. Much of the literature focuses on macro-level proxies for intergovernmental connectivity. These proxies outline broad diffusion patterns without specifying the micro-level mechanisms that govern how individuals facilitate that diffusion. The role of stakeholders in diffusion in the policy subsystem is also poorly understood. We construct a panel dataset covering the spread of the US ecotourism programs from 1993 to 2016 to investigate how micro-level movement within stakeholder networks explains state-level policy diffusion over time. Using fixed-effects regression, we find that stakeholder movement significantly drives diffusion, acting as a mechanism of knowledge transfer. Our findings provide a more precise theoretical understanding of how policy knowledge diffuses at the micro level, empirically explain the role of policy stakeholders in diffusion, and highlight the value of citizen-science data for policy research.
