I'd love to hear your opinion on what this means, not only for Medicaid, but for this broad swath of federal programs that use incentives to get cooperation from the states.

My initial reaction is it probably isn't going to mean a whole lot for the Medicaid expansion in the Affordable Care Act, because the Medicaid expansion is such a good deal for the states. You'll probably hear a lot of complaining about it, and then quiet acceptance by the complaining states.

The $64,000 question as to Medicaid is how many states are going to decide that they don't want to cover this expanded population, even with the very substantial financial incentive.

I think the bigger concern is for other cooperative federal spending programs. This is the first time the Supreme Court has ever invalidated a condition on federal spending on the grounds that it coerced the states. That's a big deal. That's a really big deal. The court has a couple times in the past suggested that there might possibly be a condition that's coercive. But it's never found something coercive until now.

The grounds on which they found this Medicaid expansion to be coercive are not entirely easy to figure out. But they are problematic for other federal spending laws, for other cooperative federal programs. I could foresee, and I do foresee, that there will be a number of challenges over the next months and years to a number of cooperative federal spending programs, like the Elementary and Secondary Education Act, particularly depending on what changes ultimately get made to No Child Left Behind and what kind of regulations get imposed on states for federal education funds. I think there could be challenges to the Individuals with Disabilities Education Act. There could be challenges to the civil rights statutes that impose conditions on the states that accept federal funds, like the Rehabilitation Act, which prohibits disabilities discrimination. So there are lots of possibilities that are opened up by this ruling to challenge well-entrenched cooperative federal spending programs. Those opportunities didn't exist before today because the court had never a condition on federal spending coercive to the states.

If this part of the ruling were its own separate decision, it would be a landmark case in the history of federalism jurisprudence. Or that's how it seemed to me. Do you agree?

So it is a fractured opinion, there is no majority opinion on the question. So we don't know exactly how much of a watershed this will be. But yes, I will say that if the Medicaid issue were not in the same case as the individual mandate, people would be talking today about what looks like a very significant decision to potentially significantly limit federal conditional spending power, absolutely.

We still have to work out exactly what it means. But it is seven justices who voted to conclude that Congress has coerced the states by threatening to take away Medicaid funds from states that don't want to expand Medicaid.