If the Supreme Court does decide to strike down any or all of the Affordable Health Care Act, the implications will range from the political to the medical to the economic.



For me, such a decision will take its place among the more supremely ironic of unintended consequences: a law designed to avoid greater government intrusion into health care will have been invalidated as an unconstitutional overreach of government power, while a far more intrusive approach would have clearly passed muster.



How could this be possible? Welcome to the wonderful world of constitutional interpretation.



Let’s begin by imagining that Congress and the president decided to adopt a genuinely radical health care plan—the kind in place in most of the industrialized world. They decide on a “single-payer” system, where the government raises revenue with taxes, and pays the doctor, hospital and lab bills for just about everyone.



Put aside the question of whether this is a good idea, or an economically sustainable notion. The question is: would such a law be constitutional?



The answer, unquestionably, is “yes.” In fact, it would be the simplest law in the world to enact. All the Congress would need to do is to take the Medicare law and strike out the words “over 65.” Why is it constitutional? For the same reason Medicare and Social Security are: the taxing power. Its reach is immense. During World War II, the maximum income tax rate was 91 per cent (it was paid by few, thanks to loopholes, but still). The same Congress that could abolish the estate tax could set just about whatever limit it chose; it could impose a 100 percent tax on estates over, say, $5 million. If it decided that a national sales tax was an answer to huge budget deficits, it could impose one at whatever level it chose.



(The remedy, of course, lies with the voters, who would be more than likely to send a powerful message at the next election, which is why the lack of constitutional limits on the taxing power do not lead to confiscatory rates.)



[Related: Romney pushed for individual mandate in Mass.]



So why is Obama’s health care plan, with a far more modest use of government power, in serious jeopardy? It’s because the key element in the plan—the “mandate” to purchase health insurance or pay a penalty—was not based on the taxing power, but on Congress’s power, under Article I, Section 8, to regulate interstate commerce. And that power, while broad, has its limits...even if those limits are murky.



Up until the late 1930s, those limits were more like shackles. The Supreme Court repeatedly struck down state and federal laws regulating wages, hours and working conditions on the grounds that the commerce power only touched the distribution of goods, not their manufacture. But once the court changed its mind—after an effort by FDR to “pack” the court with additional justices had failed—there seemed to be no limits at all. Back in 1942, the court said the government could stop a farmer from growing his own wheat for his own use, because of the potential effects on the wider market. But in 1995, for the first time in decades, the court said “no” to a federal law based on the Commerce clause—one banning firearms within school zones—because it could find no reasonable connection between the law and interstate commerce.



[Related: Biggest insurer to keep parts of health law, regardless of ruling]



In the health care case, the questioning by several justices indicated strong skepticism about the mandate. If the commerce clause can compel a citizen to buy a specific product—in this case, health insurance—what couldn’t it do? Could it, as the now famous question had it, compel citizens to buy broccoli on health grounds? (Well, a defender might have pointed out, the government does compel taxpayers to “pay for” all kinds of things in the form of government subsidies, such as ethanol. It could clearly do the same with a broccoli subsidy.)



As a policy matter, it’s clear that a “mandate” is a much more modest extension of government power than a single-payer system. The citizen would choose which insurance to buy; in fact, under the law, a citizen could choose not to buy any insurance, and pay a penalty instead. The whole premise of a mandate is to spread risk as widely as possible; as Mitt Romney used to note when he was defending the Massachusetts plan he designed, the mandate to prevent “free riders” from benefiting from treatment once they are sick or injured. That’s why the genesis of the idea came from such conservative roots as the Heritage Foundation.



[Related: Two-thirds of Americans want health law struck down]





As a constitutional matter, however, the idea of compelling a citizen into a specific economic activity raises alarm bells. It evokes the specter of some bureaucrat inviting himself into your home, while checking the shelves to make sure you’ve purchased multigrain cereal and cage-free eggs. (It’s a specter the administration tried to avoid by arguing that the health-care market is unique, one in which we are all likely participants at some point, voluntarily or otherwise. Unlike life in a Robert Heinlein libertarian “utopia,” hospital ERs do not have the power to say to an uninsured heart attack or auto accident victim: "you chose not to buy insurance? Sorry...have a nice day.”)



So, for its effort to design a health care plan that moved in the direction of less government intrusion, the Obama administration faces the distinct prospect of having its signature domestic program shot down for exceeding the limits of the constitutional power it did choose to use.



I somehow doubt the White House will appreciate the irony.





























































