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The Supreme Court’s decision on the constitutionality of the Patient Protection and Affordable Care Act (ACA) is a landmark on the path toward ensuring universal access to health care in the United States. In a 5-4 decision written by Chief Justice Roberts, the Court upheld the law in its entirety with the sole exception that Congress may not revoke existing state Medicaid funding to penalize states that decline to participate in the Medicaid expansion under the ACA. In this O’Neill Institute Briefing, we explain and analyze the Court’s decision, focusing on the individual purchase mandate and the Medicaid expansion, while also explaining the fundamental shifts in constitutional interpretations that may affect public health, safety and environmental protection in the future.

The precise significance of the individual mandate to the proper functioning of the ACA remains to be seen, primarily because the penalties are small relative to the cost of insurance. The IRS also has little enforcement authority if individuals elect not to purchase insurance. The mandate remains the only mechanism for the ACA’s financial sustainability.

The importance of the Medicaid expansion cannot be overstated, as it is the sole means by which poor Americans will gain coverage. If states decline to participate there may be a social justice disaster in which disparities in access to health insurance in some states actually widen under the ACA as middle-class and well-off Americans gain access to insurance while the poor are left behind.

Justice Roberts sided with the Court’s conservative wing to espouse a narrow view of Congress’ ability to regulate under the Commerce Clause, which could create challenges as future Congresses seek to address national public health problems. Even so, we conclude that the Court’s decision leaves the United States immensely better off in that future debates will likely center around how to ensure access to health care for all, not whether to do so–that debate is over, and the nation should push forward on the path toward universal coverage.


O'Neill Institute Briefing Paper