A Law Born Under Fire
Few pieces of legislation in modern American history have faced as sustained a legal and political assault as the Affordable Care Act. From the moment President Obama signed the ACA into law in March 2010, opponents pursued every available avenue to limit, repeal, or invalidate it. Despite those efforts, the law's core architecture remains intact — though significantly amended. Here is a condensed timeline of the major battles.
2010: Passage and Immediate Legal Challenges
The ACA was signed into law on March 23, 2010. Within hours, attorneys general in more than a dozen states filed lawsuits challenging the constitutionality of the individual mandate — the requirement that most Americans obtain health insurance or pay a penalty. The core legal question: Did Congress have the authority under the Commerce Clause to compel individuals to purchase a product?
2012: NFIB v. Sebelius — The First Supreme Court Test
In National Federation of Independent Business v. Sebelius, the Supreme Court upheld the individual mandate — but not under the Commerce Clause as the government argued. Chief Justice John Roberts, writing for the majority, held that the mandate was valid as an exercise of Congress's taxing power. The penalty for not obtaining insurance, he reasoned, was effectively a tax.
The Court also ruled that the ACA's requirement that states expand Medicaid or lose all federal Medicaid funding was unconstitutionally coercive, making expansion effectively optional.
2014: King v. Burwell and Subsidy Eligibility
This case challenged whether premium tax credits could be provided to enrollees in states that used the federal marketplace (Healthcare.gov) rather than building their own state exchange. The law's text referred to subsidies for those enrolled "through an Exchange established by the State" — language opponents argued excluded federal marketplace enrollees.
In June 2015, the Supreme Court ruled 6-3 in favor of the Obama administration, holding that reading the provision in context made clear that subsidies were available on all exchanges, state and federal. Had the Court ruled otherwise, millions of enrollees in dozens of states would have lost financial assistance.
2017: The Congressional Repeal Effort
With Republican majorities in both chambers and a new administration, 2017 brought the most serious legislative threat to the ACA. The House passed the American Health Care Act (AHCA) in May 2017, which would have repealed and replaced major ACA provisions. The Senate effort collapsed in July 2017 when three Republican senators — John McCain, Susan Collins, and Lisa Murkowski — voted against the "skinny repeal" bill.
Congress did succeed in zeroing out the individual mandate penalty through the Tax Cuts and Jobs Act of 2017, effective January 2019.
2018–2021: Texas v. United States and the Third Supreme Court Round
After the mandate penalty was reduced to zero, a group of Republican state attorneys general argued that the mandate — now raising no revenue — could no longer be justified as a tax, and that because the mandate was inseverable from the rest of the law, the entire ACA must fall.
A federal district court judge in Texas agreed; the Fifth Circuit Court of Appeals partially agreed. The case reached the Supreme Court as California v. Texas. In June 2021, the Court dismissed the challenge 7-2 on standing grounds, ruling that plaintiffs had not demonstrated sufficient injury to bring the case — leaving the ACA intact without resolving the underlying constitutional question.
2022: American Rescue Plan and Inflation Reduction Act Expansions
Rather than repeal, Congress moved toward expansion. The American Rescue Plan Act of 2021 temporarily increased and expanded ACA premium tax credits, eliminating the 400% FPL income cap for subsidy eligibility. The Inflation Reduction Act of 2022 extended those enhanced subsidies through 2025, significantly increasing marketplace enrollment.
Looking Ahead
As the enhanced subsidies approach their expiration date, Congress faces a decision: allow them to lapse, extend them again, or make them permanent. Meanwhile, proposals to restructure Medicaid financing and revisit ACA regulations remain active in policy circles. The ACA's legal and legislative saga is almost certainly not over.