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American Politics | Health Policy | Models and Methods | Political Science


Claire Haeg, Political Science


In 2009, the Patient Protection and Affordable Care Act became law. This was possible because the Democratic Party had a majority in both branches of Congress and control in the executive branch. In 2017, the American Health Care Act failed to become law, despite the fact that the Republicans controlled Congress and the presidency. What factors explain the different outcomes? Why was one able to pass, but not the other? This study presents a framework for explaining these different outcomes by exploring the impact of the legislative process, the role of public opinion, and the impact of polarization as factors that influenced both legislative outcomes. Using process tracing this study examines the impact of unorthodox lawmaking, public opinion data on healthcare, and DW-Nominate scores as a measure of polarization. The results show that a combination of factors impacted the legislative outcomes on these two major bills. The findings suggest that a holistic approach to examining factors is useful when explaining why a piece of major legislation is passed or failed.


This paper uses process tracing, public opinion, and factionalism measures to determine why two congresses in similar structural situations were unable to both pass sweeping healthcare reforms.