Earlier today, I blogged the syllabus of the majority opinion, and noted my earlier thoughts that the statute is likely constitutional. I mentioned that I might have more thoughts after I read the opinions, so here are those thoughts — but note that they’re brief and rather shallow, since I’m not a scholar of federal power or federal-state relations (I focus more on the specific individual rights guarantees):
1. I have tentatively come around to Justice Thomas’s dissenting view, which is largely joined by Justice Scalia. I think he’s probably right that Congress’s having the enumerated power to imprison someone for a crime — for instance, the power under the Commerce Clause to punish crimes that interfere with interstate commerce, or the power under the Post Office Clause to punish crimes against the mails — does not extend to protecting state citizens after the person is released following the expiration of its term. That should be a matter left to the states. And despite the majority’s and concurrences’ suggestion that the states may be unable or unwilling to lock up people who are dangerous (whether because they are insane, or because they have been found to be sexually violent predators), I think Justice Thomas is probably correct that this assertion is both factually mistaken and legally irrelevant.
2. Unlike the Kennedy and Alito concurrences, which at least stress the importance of constitutional limits on federal power — though they disagree with Thomas and Scalia about whether those limits were transgressed here — the majority has pretty broad language in support of nearly unlimited federal authority. And this language was joined by Chief Justice Roberts, and not just the four liberals. This suggests that the brief resurrection of the enumerated powers doctrine, under which courts would strike down some Congressional actions as going beyond the constitutionally granted powers (even without regard to, say, the First Amendment or similar express rights guarantees), may be largely over.
In the mid-1990s, United States v. Lopez, United States v. Morrison, and Boerne v. City of Flores did set aside Congressional action on those grounds. But more recently Gonzales v. Raich (the medical marijuana case) and this case cast doubt on that revival.
To be sure, the facts of this case are unusual, because the law here applies only to people who had already been convicted of federal crimes. But the majority’s rationale seems quite broad; it concludes that federal power challenges should be upheld so long as they are “rationally related to the implementation of a constitutionally enumerated power” — that’s the famously extremely deferential “rational basis” test. And while it acknowledges, citing Lopez, that a statute might be unconstitutional if “the links between [it] and an enumerated Article I power are ... too attenuated,” the majority stresses that even quite indirect connections can qualify as “not too attenuated.”
As Randy points out, this doesn’t deal with the question whether some laws are unconstitutional because they fail the “proper” prong of the “necessary and proper” clause. It’s also possible that Chief Justice Roberts will in a later case take a view that’s more constraining of federal power; it’s hard to confidently predict a Justice’s views based on one case. And, as I said, the statute involved here is somewhat peculiar, so a future Court might distinguish the case on the facts, and not focus too much on the broad reasoning. Still, the majority opinion, and Chief Justice Roberts’ signing of the opinion, aren’t good signs for the prospect of further judicial enforcement of the enumerated powers doctrine.