State Treaties

No State shall enter into any Treaty, Alliance, or Confederation; grant Letters of Marque and Reprisal....

Article I, Section 10, Clause 1

In addition to granting the government powers to regulate trade and raise revenue that it either lacked or could not enforce under the Articles of Confederation, the Framers intended the Constitution to centralize much, if not all, power over foreign affairs. Many of the federal government's enumerated powers relate to foreign affairs and have corresponding restrictions on states in Article I, Section 10. Article VI of the Articles of Confederation had permitted the states to conclude treaties with foreign governments with the consent of Congress. States could also grant letters of marque and reprisal after Congress had declared war. While some of Article I, Section 10's proscriptions, like the ability to levy tonnage duties or enter into "compacts or agreements," may be permitted by Congress, others, like the prohibitions described here, are absolute.

Treaties, as well as alliances and confederations, are formal, binding agreements between nations that are the subjects of international law. "Compacts and agreements" are usually made by governmental officials, such as the executive, or by subsidiary governmental units, such as states or municipalities. In the late eighteenth century, governments issued letters of marque and reprisal to authorize private ships to attack certain foreign shipping and gain booty for their efforts. Issuing them was regarded as an act of war.

In The Federalist No. 44, James Madison noted that these proscriptions (like the prohibition on treaties) either "need[ed] no explanation" or (like the restrictions on letters of marque and reprisal) were "fully justified by the advantage of uniformity in all points which relate to national powers; and of immediate responsibility to the nation in all those for whose conduct the nation itself is to be responsible." Justice Joseph Story concurred, writing in his Commentaries on the Constitution of the United States that the state marque and reprisal restriction "is appropriately confined to the national government" because "the protection of the whole Union is confided to the national arm, and the national power," and no state "should possess military means to overawe the Union, or to endanger the general safety." As noted foreign-affairs scholar Louis Henkin remarked, "these restrictions are as clear as words can make them and have raised no issues...."

The courts have had little occasion to deal with the clause, though in Holmes v. Jennison (1840), Justice Roger B. Taney, writing for himself and three other Justices, commented that the clause "positively and unconditionally" forbade states from entering into treaties, and that "even the consent of Congress could not authorize" them to do so. He also distinguished formal "treaties," which were expressly forbidden to states, from "agreements" and "compacts" that Congress could authorize.

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Brannon P. Denning
Professor of Law
Cumberland School of Law, Samford University