This paper estimates the causal impact of Democratic vs Republican governors on pollution. Using a regression discontinuity design, gubernatorial election data, and air quality data from US Environmental Protection Agency (EPA), we find that air pollution is lower under Democratic governors.

Political parties, Pollution, Regression discontinuity
dx.doi.org/10.1016/j.econlet.2015.11.007
Economics Letters

Beland, L.-P., & Boucher, V. (Vincent). (2015). Polluting politics. Economics Letters, 137, 176–181. doi:10.1016/j.econlet.2015.11.007