He may be a staunch conservative, but the justice understands the commerce clause better than anyone else on the Supreme Court.
Most non-lawyers have been bemused by the confidence that constitutional lawyers once had about the Supreme Court's likely decision in the Patient Protection and Affordable Care Act (aka, the Obamacare) case. The idea that this Republican Court would not give the Republicans their victory seemed silly to most, or at least naive. What possible reason would there be to imagine the Court would hold its punches?
But indeed, there was a confidence, at least among those whose career is focused upon the intricacies of commerce clause jurisprudence, that the Court would uphold the statute. When I read that my colleague Charles Fried -- Ronald Reagan's solicitor general -- said that he would eat his hat if the Court struck the statute, I didn't think Fried was being brave or reckless: the point seemed too obvious to remark. Whether wise or not, Obamacare is plainly constitutional under the Court's existing precedents. That's not to say the Court couldn't make up a new rule by which the law was deemed unconstitutional. But against the history of the repeated embarrassments that the Court has suffered as it has tried to police Congress' commerce authority, it seemed genuinely unimaginable that it would again make the same mistake.
The simplest way to see this point is to focus on the jurisprudence of a key vote in any hypothetical 5-4 decision to strike the law -- Justice Antonin Scalia.
Scalia's commerce clause jurisprudence is among the most careful, and, in my view, precise among the justices likely to impose a constitutional limit on Congress' authority. His concurring opinion in Gonzales v. Raich, a case about whether Congress had the power to regulate home-grown marijuana, maps a very clear formula for testing Congress's authority. If you apply that test to Obamacare -- especially in light of the evidence just published by my colleague Einer Elhauge -- there can be little doubt about the answer.
Under Scalia's approach, the question of Congress's authority is not answered by asking whether the activity regulated is, or affects, interstate commerce. Though that clause only gives Congress the power to regulate "commerce among the several states," as Scalia said in Raich, Congress's power is supplemented by the Constitution's "Necessary and Proper Clause" power. That clause means that "Congress may regulate even those intrastate activities that do not themselves substantially affect interstate commerce," at least if such regulation is "Necessary and Proper" to Congress' commerce power or to any other power granted the federal government. In other words, Congress can regulate an activity that is not interstate commerce so long as regulating it is "Necessary and Proper" to Congress' regulating interstate commerce.
Whether a regulation is "necessary and proper" is a question Scalia has also answered carefully. While the Court since the early 19th century has read "necessary" very loosely, Scalia has insisted that a regulation must also be "proper." And while the full scope of that propriety has not yet been clearly set, it is at least the case, Scalia has insisted, that the regulation should not conflict with other constitutional values, or with longstanding tradition. If it does, then it would fall outside Congress' power.
The Obamacare case forces the Court to decide whether the power to regulate "activities" that are, or might substantially affect "commerce among the several states" could also include the power to regulate "non-activities" -- the failure to buy health insurance -- that likewise affect "commerce among the several states."
For less nuanced theories, this question presents a puzzle. How can a non-activity be regulated by a clause that gives Congress the power to regulate "commerce" -- quintessentially an "activity"?
But for Scalia's theory, there is no puzzle. Just as intrastate activities that don't substantially affect interstate commerce can be regulated, on Scalia's account, if "Necessary and Proper" to some commerce-clause end, so too should Congress have the power to regulate non-activities, so long as they are "Necessary and Proper" to some commerce-clause end.
No one doubts that under the current Court's reading of "necessary," the alleged effect of this non-activity -- the failure of some to buy insurance -- substantially affects interstate commerce. The only question for Scalia -- and he made this question clear in oral argument -- is whether regulating a non-activity is also "proper." Put most strongly, at least for an originalist: is there evidence that the Framers would have deemed "improper" a law that forced citizens to do something they didn't want to do or to buy something they didn't want to buy? Or again, is there evidence that the Framers would have channeled Justice Brandeis by protecting a fundamental "right to be left alone," economic efficiencies notwithstanding?