Several commentators have been highlighting an important but largely overlooked aspect of yesterday's Supreme Court health-care ruling: the decision related to the expansion of Medicaid.

Under the Affordable Care Act, states are encouraged to expand Medicaid coverage; to make it attractive for all states to do that, the federal government will pay the full cost of the expansion for the first three years, and will cover 90 percent of the cost after that.

But until yesterday's ruling, there was a severe penalty: If states didn't expand their Medicaid coverage, the federal government would withhold all Medicaid funding, even funding unrelated to the expansion. Seven of the nine justices agreed that the government can't do that.

Some commentators have worried that the ruling makes it likely that many states will not participate in the expansion, leaving millions of Americans still without health-care coverage. But on scotusblog today, Kevin Russell adds another concern: Yesterday's court ruling, he writes, may open the door to states suing to get out of other federal programs that have carried similar penalties.

Among them, he writes: "Title IX (sex discrimination in federally funded education programs), Title IV (race discrimination in any federally funded program), and the Rehabilitation Act (disability discrimination in federally funded programs)."

Russell concludes that it probably isn't likely that the Supreme Court would strike down those older laws. But, he adds, "I would not be surprised to see some lower courts holding the statutes unconstitutional, and I would be shocked if states did not ask them to do so."