Constraints on policy learning: designing the Regional Greenhouse Gas Initiative in Pennsylvania

Abstract Much policy diffusion and learning research examines macro-level patterns of policy spread. However, micro-level case studies can reveal nuances in how learning occurs, particularly when innovation originates within the executive branch, not the legislature. This case study of Pennsylvania’s effort to join the regional greenhouse gas initiative (RGGI) illuminates the legal constraints faced by administrators who must innovate within the bounds of existing authority. The study also shows that legal constraints can reduce an agency’s ability to maximize the political durability of major policy reform. The case yields insights for both policy designers and scholars of policy diffusion and learning.