One of those decisions could come in June in the Supreme Court case known as King v. Burwell. In that case, plaintiffs are challenging the legality of federal subsidies given to customers of HealthCare.gov, the federal Obamacare insurance marketplace that now serves 37 states.
Without those subsidies, more than an estimated 8 million people, primarily adults, would lose their health insurance in 2016 because they would no longer be able to afford health insurance at its nonsubsidized price.
But Dubay said that a decision for the plaintiffs in the King case alone threatens to lead to 600,000 kids becoming uninsured.
And such a decision would be exacerbated if Congress does not reauthorize funding for CHIP, and again if Congress, as proposed, lifts the requirement that states maintain their current eligibility for Medicaid to children whose families earn 138 percent of the federal poverty level, according to the Urban Institute. Without reauthorization, CHIP funding ends in September.
Dubay said that "in theory, it's very likely that CHIP would be reauthorized" because there is support for the program among Republicans in Congress as well as Democrats.
But in actuality, the current Congress has had difficulty getting bipartisan consensus on several big issues.
"Everyone wants to do it, so it's going to get done? That doesn't always happen," Dubay said.
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Dubay said she thinks that that the worst-case scenario envisioned by the report, the one in which 3.3 million kids become uninsured, is "very unlikely." That's because, she said, it assumes that all the states that could do so would restrict Medicaid eligibility for kids to only the ones whose families are under 138 percent of the poverty line.
But, she said, it's "not out of the realm of possibility" that nearly 2 million kids become uninsured because of a decision in King by the high court, and due to Congress not reauthorizing CHIP.
"That is something I worry about happening," Dubay said. "That could be the outcome of a sort of political logjam and a finding for the plaintiffs."