Published online by Cambridge University Press: 18 June 2019
Although energy policy used to be a nonpartisan issue in Congress, partisan conflicts over energy policies are intense these days. To examine how a nonpartisan issue became a highly partisan one, we create and use a new measure of energy policy positions of members of Congress. Our analyses of member behaviour show that, in addition to partisan realignment in the South, energy policy-specific factors – rising oil prices, the climate change debate since 1988, and the salience of energy policy in Congress – are significantly related to increasing party polarisation over energy policy. We also find that the increasing convergence between energy policy and environmental policy has significantly contributed to party polarisation over energy issues. The study thus provides important understanding of this specific policy area as well as insights into the party polarisation literature by demonstrating how policy-specific events and policy convergence transform a nonpartisan issue into a highly partisan one.