1. Whether the Anti-Injunction Act bars a challenge to the individual mandate at this time.
As Armando initially explained, the AIA is an 1867 law which says that you can't sue the government to prevent it from assessing a tax against you; you have to wait to be taxed, and then you can challenge it. So, if the mandate is a "tax," a challenge to the mandate can't be heard until 2014-15. Both the 4th Circuit and conservative stalwart DC Circuit Judge Brett Kavanaugh bought this argument, even though the parties themselves didn't advocate for it, and the Supreme Court appointed outside counsel to advocate this view before it.
After oral argument, I didn't think the justices were persuaded by this argument. That said, in her American Constitution Society address on June 15, Justice Ginsburg did joke that this was the issue which America was waiting for, so ... who knows?
[If the Court finds the AIA applicable, skip to 4.]
2. Is the Minimum Coverage (individual mandate) provision constitutional?
The big question. Either the Court deems the requirement to be within the necessary and proper powers of Congress in tackling a national problem which clearly affects interstate commerce, or it can overturn precedent going as far back as McCullough v. Maryland (1819), which proclaimed: "Let the end be legitimate, let it be within the scope of the constitution, and all means which are appropriate, which are plainly adapted to that end, which are not prohibited, but consist with the letter and spirit of the constitution, are constitutional."
And as we all know, oral argument made a ruling of unconstitutionality seem likely, with Justice Scalia's fortuitous flip-flop on the Wickard precedent depressing hopes further. All I'm willing to say right now is that it's more likely than not that the individual mandate will fall, and the folks on Intrade agree.
[If the Court finds the mandate constitutional, skip to 4.]
3. If the Minimum Coverage provision is unconstitutional, what else must go?
This is the severability question. Because the ACA itself did not contain a provision expressing what should happen should any provision be struck down, it's for the Court to decide. There are three options: (a) everything must fall, because the ACA would not have passed without the mandate and it's better to let Congress figure out what Congress wants without a mandate (the opponents' position); (b) the Guaranteed Issue (preexisting conditions protection) and Community Rating provisions must fall, because they're inextricably intertwined with the mandate (the government's position); or (c) everything else still stays (a position argued by no party, but argued by an amicus brought in by the Court).
I still expect this issue to greatly divide the Court, and it's here, I think, that the chief justice and Justice Kennedy may endeavor to hold some center together and let most of the bill stand.
[If the answer to 3 is (a), skip question 4. You're done. Otherwise ... ]
4. Does the Medicaid expansion constitute unconstitutional coercion of state governments?
Unless the whole bill falls, the Court will have to answer this question regardless of its answers on the Anti-Injunction Act and the mandate: Were the conditions placed on the states via ACA's expansion of Medicaid coverage so coercive as to be unconstitutional? I didn't think this argument grabbed five votes at oral argument, but the Court's five conservatives are full of surprises.
What else to expect: There will likely be many opinions issued as part of this decision; I've set the over/under at 5.5. Pay careful attention as to which parts of which opinions have the support of at least five justices; that's what controls. As Justice Brennan explained to his clerks every year, the most important rule of constitutional law they needed to understand was the Rule of Five: With five votes, the justices can do anything. And this week, they will.