 | This article needs additional citations for verification .(October 2025) |
A plenary power or plenary authority is a complete and absolute power to take action on a particular issue, with no limitations other than what is prescribed by the constitution. It is derived from the Latin term plenus , 'full'. [1]
There are very few clear examples of such powers in the United States, due to the nature of the Constitution, which grants different, but at times overlapping, roles to the three branches of federal government and to the states. For example, although the United States Congress, under Article I, Section 8, Clause 3 (the Commerce Clause), has been said to have "plenary" power over interstate commerce, this does not always preclude the states from passing laws that affect interstate commerce in some way. When an activity is legally classified as interstate commerce, historically the states can regulate this type of activity as long as they do so within the bounds of their constitutional authority. [2]
Chief Justice John Marshall emphasized in Gibbons v. Ogden that the interstate commerce power was plenary and preempted state regulations when they came into conflict: [3]
This power, like all others vested in Congress, is complete in itself, may be exercised to its utmost extent, and acknowledges no limitations other than are prescribed in the constitution.
Another example of the ongoing debate over plenary powers in the U.S. Constitution is the controversy surrounding the Spending Clause (Article I, Section 8, Clause 1). This clause states that the Congress is allowed to "lay and collect Taxes, Duties, Imposts and Excises, to pay the Debts and provide for the common Defence and promote the general Welfare of the United States". How far this clause goes, and what it actually means in practice, has been hotly debated since the ratification of the Constitution. [4]
While other Constitutional doctrines, such as the unenumerated powers of states and the rights of individuals, are widely held (both historically and currently) as limiting the plenary power of Congress, [5] then-Associate Justice William Rehnquist reflected that "one of the greatest 'fictions' of our federal system is that the Congress exercises only those powers delegated to it, while the remainder are reserved to the States or to the people.
Congress and the President have plenary power to make and enforce immigration and nationality policy, with limited judicial review. [6] This power is foregrounded in the "ancient principles of the international law of nation-states", [7] or Ius gentium principles, that immigration and nationality laws are matters of sovereignty; that immigration and naturalization are privileges that exist at the pleasure of the people; and that immigration and nationality laws involve political questions best left to the people. [8] Though this power was largely unused until the 1880s, the underlying principles behind it trace as far back as the Roman Empire and were embraced by Founding Fathers such as Gouverneur Morris, who is quoted as stating: "Every society, from a great nation down to a club, had the right of declaring the conditions on which new members should be admitted." [9] The textual basis of this lies in the foreign affairs powers under the commerce, naturalization, define and punish, and war clauses of the Constitution. [10] [11]
Congress has power over Indian affairs under article I, section 8, clause 3 of the Constitution, or the Commerce Clause: "To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes." [12] The scope of this power is plenary and works to the exclusion of states or tribes, with Congress even able to de-establish a tribe itself. [13] Many tribal leaders view this power over their affairs as tyrannical, since it inhibits self-governance and subjects them to outside forces in Congress. [14]
Congress has power over the postal system under article I, section 8, clause 7, or the Postal Clause: "To establish Post Offices and post Roads." The scope of this power is plenary and is not affected by federalism concerns under the Tenth Amendment. [15]
However, the plenary power doctrine is firmly rooted in the Anglo-American legal tradition. It should be emphasized that the determination to expel or exclude foreigners, whether they have already lawfully settled or even begun the process of naturalization, is a political question and not a vested right absent congressional statutory acquiescence...It is an issue that can only be placed into this nation's political discourse, where it has always and rightfully been.
Stemming from 'ancient principles of the international law of nation-states,' '[t]he power to admit or exclude is a sovereign prerogative.' Indeed, the ability to 'regulate the flow of non-citizens entering the country . . . is an inherent power of any sovereign nation.' This idea traces as far back as the Roman Empire and 'received recognition during the Constitutional Convention.'
Notably, the Constitution does not expressly grant the federal government wholesale foreign affairs power. The foreign affairs power, rather, appears to be an amalgamation of Congress's powers to 'regulate commerce with foreign nations, to define offenses against the law of nations, and to declare war'…One more provision rounds out constitutional support for federal immigration powers: the naturalization provision that grants the federal government the power to 'establish an uniform Rule of Naturalization,' or a law for granting naturalized citizenship.
[Founding era authorities on the law of nations, such as] Pufendorf, Barbeyac, Vattel, Martens, Blackstone, and—more obliquely, Grotius and Burlamaqui— all addressed limits on immigration when writing on the law of nations. These authors consistently recognized the prerogative of governments to impose immigration restrictions. That prerogative was qualified in cases of necessity (for example, a ship being driven by storm onto a foreign shore), and in the cases of exiles and fugitives. As to voluntary immigrants, however, all but Grotius—the earliest of the writers— recognized that the power to restrict was nearly absolute.
Within the field of functions properly promoted by the postal system Congress' power is plenary and whether Congress may deal directly with a situation in that area or not, the Tenth Amendment ought not restrict the power of Congress.