Andrew Koppleman’s article on “The Obvious Constitutional of Health Care Reform” contains a very useful primer on the McCullough v Maryland decision and the general concept of “necessary and proper.”
The list of congressional powers in Article I ends with an authorization to “make all Laws which shall be necessary and proper” to carry out its responsibilities. The interpretation of this provision was settled in 1819 by Chief Justice John Marshall in McCulloch v. Maryland. The central question in McCulloch was whether Congress had the power to charter the Bank of the United States, the precursor of today’s Federal Reserve Bank. The Constitution does not enumerate any power to create corporations. The State of Maryland, which was trying to tax the Bank out of existence, argued that the “necessary and proper” language permitted Congress only to choose means that were absolutely necessary to carry out those powers. Marshall rejected this reading, which would make the government “incompetent to its great objects.” The federal government must collect and spend revenue throughout the United States, Marshall observed, and so must quickly transfer funds across hundreds of miles. “Is that construction of the constitution to be preferred which would render these operations hazardous, difficult, and expensive?” Without implied powers, Congress’s power “to establish post offices” could not entail the ability to punish mail robbers and might not even entail the power to carry letters from one post office to another. “It may be said, with some plausibility, that the right to carry the mail, and to punish those who rob it, is not indispensably necessary to the establishment of a post office and post road.” He concluded that Congress could choose any convenient means for carrying out its enumerated powers.
And there’s the rub. Regulating health insurance firms is clearly part of regulating the national economy, and the individual mandate to purchase health insurance (or get insurance from your employer or be enrolled in Medicare or Medicaid or another public sector health insurance program or pay a fine or get a hardship waiver) is clearly part of regulating the health insurance industry. The only genuine question here is whether we want to throw out decades of doctrine and say that congress doesn’t actually have general authority to regulate the economy.