Party Polarization on Environmental Voting in the U.S. Congress

• In Event: Comparative Party Polarization

Abstract

We examine the puzzle of party polarization in the US Congress with a focus on environmental legislation since 1970. The puzzle of polarization stems from three sources. First, environmental polarization has not always been present. At the advent of the modern environmental movement in the 1970s, federal legislation was bipartisan. Second, evidence from the Environmental Kuznets Curve literature (Grossman and Krueger 1995, and Copeland and Taylor 2004) suggests that higher income leads to higher demand for environmental quality, which suggests Republican legislators would be at least as likely to provide support for pro-environmental legislation (Republican voters have tended to have higher average incomes than Democratic voters). Third, voters tend not to be as polarized as legislators on environmental issues (as indicated in polls such Gallup 2021, Barber and McCarty 2015). To examine this puzzle we developed a theoretical framework that extends electoral competition models by incorporating new interest groups into political parties, and explains the rise in environmental polarization, the role of interest groups in mitigating the effects of income on environmental voting, and the role of party in shaping votes. Our empirical analysis combines data on congressional environmental votes from 1971 to 2016 with data on legislator characteristics, congressional district economic and demographic information, and interest group contributions. Results from a regression discontinuity design confirm that party polarization emerged over time from initial bipartisanship, but also finds evidence that economic and party forces play a role in environmental voting. We find that polarization decreases in legislative districts more dependent in “brown” industries and increases as legislative districts’ income increases. Polarization also increases if legislators have leadership positions in Congress or if they are in their first year in office.

Authors

• Dean L Lueck, Indiana University

• Julio A. Ramos Pastrana, The Pennsylvania State University

• Gustavo F Torrens, Indiana University