This artist rendering shows Chief Justice John Roberts, center, speaking… (Dana Verkouteren / Associated…)
Today we resolve constitutional challenges to two provisions of the Patient Protection and Affordable Care Act of 2010: the individual mandate, which requires individuals to purchase a health insurance policy providing a minimum level of coverage; and the Medicaid expansion, which gives funds to the States on the condition that they provide specified health care to all citizens whose income falls below a certain threshold. We do not consider whether the Act embodies sound policies. That judgment is entrusted to the Nation’s elected leaders. We ask only whether Congress has the power under the Constitution to enact the challenged provisions.
In our federal system, the National Government possesses only limited powers; the States and the people retain the remainder. Nearly two centuries ago, Chief Justice Marshall observed that “the question respecting the extent of the powers actually granted” to the Federal Government “is perpetually arising, and will probably continue to arise, as long as our system shall exist.” In this case we must again determine whether the Constitution grants Congress powers it now asserts, but which many States and individuals believe it does not possess. Resolving this controversy requires us to examine both the limits of the Government’s power, and our own limited role in policing those boundaries.
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Today, the restrictions on government power foremost in many Americans’ minds are likely to be affirmative prohibitions, such as contained in the Bill of Rights. These affirmative prohibitions come into play, however, only where the Government possesses authority to act in the first place. If no enumerated power authorizes Congress to pass a certain law, that law may not be enacted, even if it would not violate any of the express prohibitions in the Bill of Rights or elsewhere in the Constitution.
Indeed, the Constitution did not initially include a Bill of Rights at least partly because the Framers felt the enumeration of powers sufficed to restrain the Government. As Alexander Hamilton put it, “the Constitution is itself, in every rational sense, and to every useful purpose, A BILL OF RIGHTS.” And when the Bill of Rights was ratified, it made express what the enumeration of powers necessarily implied: “The powers not delegated to the United States by the Constitution . . . are reserved to the States respectively, or to the people.” The Federal Government has expanded dramatically over the past two centuries, but it still must show that a constitutional grant of power authorizes each of its actions.
The same does not apply to the States, because the Constitution is not the source of their power. The Constitution may restrict state governments—as it does, for example, by forbidding them to deny any person the equal protection of the laws. But where such prohibitions do not apply, state governments do not need constitutional authorization to act. The States thus can and do perform many of the vital functions of modern government—punishing street crime, running public schools, and zoning property for development, to name but a few—even though the Constitution’s text does not authorize any government to do so. Our cases refer to this general power of governing, possessed by the States but not by the Federal Government, as the “police power.”
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This case concerns two powers that the Constitution does grant the Federal Government, but which must be read carefully to avoid creating a general federal authority akin to the police power. The Constitution authorizes Congress to “regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes.”Art. I, §8, cl. 3. Our precedents read that to mean that Congress may regulate “the channels of interstate commerce,” “persons or things in interstate commerce,” and “those activities that substantially affect interstate commerce.” The power over activities that substantially affect interstate commerce can be expansive. That power has been held to authorize federal regulation of such seemingly local matters as a farmer’s decision to grow wheat for himself and his livestock, and a loan shark’s extortionate collections from a neighborhood butcher shop.
Congress may also “lay and collect Taxes, Duties, Imposts and Excises, to pay the Debts and provide for the common Defence and general Welfare of the United States.” U. S. Const., Art. I, §8, cl. 1. Put simply, Congress may tax and spend. This grant gives the Federal Government considerable influence even in areas where it cannot directly regulate. The Federal Government may enact a tax on an activity that it cannot authorize, forbid, or otherwise control.