To accept the challengers' argument about congressional intent, the proposition you have to accept is this: For over a year, as Congress debated the Affordable Care Act, and for a good while after it passed, hardly anyone—Republicans, Democrats, journalists, and budget analysts—really understood how it worked, even though Congress had spelled it out clearly.
"There's just no way that we would have been having this conversation about excluding half the country from tax credits "¦ but not have had the press, our opponents, and many in Congress screaming at the top of their lungs," Fontenot said.
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That's why so many health care wonks have been so stupefied by this challenge. Because they were all there. They all lived through it. And this issue the Court will debate Wednesday just didn't come up at the time.
The Congressional Budget Office has said it never considered the possibility that subsidies might only be available in some states—and that no one ever asked it to score the law's costs under that assumption. Several states have said they were never told, while they were deciding whether to set up their own exchanges, that their decisions could deny financial assistance to their residents. Even Republicans assumed the subsidies would be available in every state.
In 2012, Republicans on the Senate Budget Committee produced a report arguing that CBO had underestimated Obamacare's costs. Accusing the budget office of "a colossal misstatement of reality," Republicans said the law would actually cost $2.6 trillion over its first decade. That figure would have been impossible to reach without the law's most expensive provision—its subsidies.
And this was in June 2012, when it was clear that most states would not be setting up their own exchanges. Only 14 states had passed bills to establish exchanges at the time of the Budget Committee's report, and health care analysts were speculating in the press that fewer than 20 states would ultimately sign on.
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Michael Cannon, the director of health policy at the libertarian Cato Institute, says it doesn't matter how many people assumed that subsidies were available in every state.
"It doesn't matter what they say about what they enacted. It doesn't matter what they understood about what they enacted," he said. "Just because an assumption is widespread doesn't mean it's true."
The challenge in King centers around a line in the statute that lays out the formula for calculating Obamacare's subsidies. It says the amount of each person's subsidy should be based on the time they were covered through "an Exchange established by the State."
To Cannon, that means the subsidies are only available in state-based exchanges—and not in the 34 states that turned to the federal government to set up their marketplaces. The challengers have had a harder time, though, persuading courts that Congress meant to limit subsidies to state-run exchanges.