Using the Environmental Scorecard ratings of Congressmen and Senators published annually by the League of Conservation Voters, we explore empirically whether political support for pro-environment legislation, aggregated across each legislative body, is sensitive over time to changing economic conditions — that is, whether there is a political trade-off between economic conditions and the environment. Using LCV scorecard ratings from 1970 to 2008, we find evidence, consistent across both the House and Senate, that political support for the environment is related to per capita income, but this general tendency can be decomposed into sharp differences by party.