A large environmental justice literature suggests that the siting of highly emitting industrial plants has historically generated inequities in exposure, often on the basis of race and socioeconomic status. Economically disadvantaged and minority communities have long experienced higher environmental disamenities, resulting in health and economic consequences. This means that policies targeting emissions reductions may disproportionately benefit disadvantaged communities, potentially reducing environmental injustices. Yet, preliminary evidence suggests that the implementation of cap-and-trade programs may yield regulatory patterns that limit both the progress towards equity and justice objectives. This project examines these patterns in the context of the Regional Greenhouse Gas Initiative (RGGI), a cap-and-trade program operating in the Northeastern and Mid-Atlantic regions of the United States. Using program reports, I examine the program’s objectives in member states, identifying themes in equity and environmental justice considerations as part of program design and implementation. Drawing on these themes, I use a difference-in-differences framework to quantitatively evaluate the impacts of RGGI’s passage and implementation on county-level measures of economic wellbeing, demographics, and population health. Comparing across states, I find suggestive evidence that counties with coal-fired power plants in RGGI states saw short-term declines in economic well-being in the years following RGGI’s implementation; these declines largely disappeared within a decade of implementation. There is also evidence of demographic shifts; these counties see increased population, particularly among non-whites and adults. Comparing within states, I find no evidence that counties with coal-fired power plants experience changes in economic wellbeing or demographics relative to their neighbors. Identifying the mechanisms underlying disparities in exposure to environmental harms is essential for designing climate policies that can promote sustainable environmental stewardship while remedying environmental injustices.