Measuring environmental policy change: Conceptual alternatives and research implications

Abstract: The study of policy change has been receiving increasing scholarly attention. Despite the growing number of empirical studies on policy change, the definition and measurement of the concept has made limited progress. In comparative environmental policy research, for instance, most existing large n studies rely on impact data such as pollutant emissions to approximate processes of policy change, often without discussing the conceptual implications of this measurement approach. Against this background, this article proposes a new measurement concept for empirically assessing environmental policy change, which conceives of policy change in terms of changes in policy outputs. We illustrate our measurement concept on the basis of an original dataset covering the evolution of clean air policies in 24 advanced democracies over a period of almost three decades (1976-2003). In a second step, we evaluate the relationship between our measurement of environmental policy change and standard emission data representing the most widely used proxy in the literature. Our findings suggest that clean air policies cannot be consistently associated with emission levels, therefore calling into question the viability of environmental impact data for the study of the determinants of policy change.;