As you'll recall, the Affordable Care Act (ACA) significantly expanded Medicaid — the War on Poverty legislation that had, for decades, provided comprehensive medical insurance to (certain) poor people.
Among other things, the ACA Medicaid expansion required state Medicaid programs to cover all adults with incomes below 133 percent of the federal poverty level. Before ACA passage, coverage generally had income and other requirements that were considerably stricter. (For instance, before the ACA, Medicaid did not cover childless adults at all, no matter how poor.)
Medicaid is a "cooperative" federal-state program in which participating states choose to accept federal funds to help pay for the program, subject to various federal requirements. All states currently participate in Medicaid in one form or another. Under the ACA, the costs of Medicaid expansion is paid for at first 100% with federal dollars and then 90% with federal dollars beginning in 2020.
As written in the ACA, Medicaid expansion was not optional. A state could quit Medicaid entirely, but if it participated, it had to expand.
But the Supreme Court held in NFIB v. Sebelius, 567 U.S. 519 (2012), that Medicaid expansion was nonetheless optional for each state because requiring states to expand — that is, requiring them to expand or leave the program entirely — was too coercive under the constitution's so-called Spending Clause. As a result of that decision, today only about 35 states and D.C. participate in Medicaid expansion. The other states do not.
With all this in mind, take a look at a new National Bureau of Economic Research study entitled Medicaid and Mortalilty: New Evidence from Linked Survey and Administrative Data by Sarah Miller, Sean Altebruse, Norman Johnson, and Laura Wherry. The study finds that thousands of poor people's lives have been improved, and poor people's deaths prevented, in states that have accepted Medicaid expansion.
And what about the states that have not accepted Medicaid expansion because it's too "coercive"? There's this:
Our analysis provides new evidence that Medicaid coverage reduces mortality rates among low-income adults. Our estimates suggest that approximately 15,600 deaths would have been averted had the ACA expansions been adopted nationwide as originally intended by the ACA. This highlights an ongoing cost to non-adoption that should be relevant to both state policymakers and their constituents. (emphasis added)