Interstate Compacts are not new legal instruments. Compacts derive from the nation’s colonial past where states utilized agreements, like modern Compacts, to resolve inter-colonial disputes, particularly boundary disputes.

The colonies and crown employed a process to negotiate and submit colonial disputes to the crown through the Privy Council for final resolution. This created a long tradition of resolving state disputes through negotiation followed by submission of the proposed resolution to a central authority for its concurrence. The modern “Compact process” was formalized under the Articles of Confederation. Article VI provided: “No two or more states shall enter into any treaty, confederation or alliance whatever without the consent of the United States in Congress assembled, specifying accurately the purposes for which the same is to be entered into, and how long it shall continue.”

Concerned with managing interstate relations and the creation of powerful political and regional allegiances, the Founders barred states from entering “any treaty, confederation or alliance whatsoever” without the approval of Congress. They also constructed an elaborate scheme for resolving interstate disputes. Under Articles of Confederation, Article IX, Congress was to “be the last resort on appeal in all disputes and differences now subsisting or that hereafter may arise between two or more States concerning boundary, jurisdiction or any other causes [.]” Later, the concern over unregulated interstate cooperation continued during the drafting of the U.S. Constitution, resulting in the adoption of the “Compact Clause,” Article I, sect. 10, cl. 3.

The Compact Clause provides that, “No state shall, without the consent of Congress…enter into any agreement or Compact with another state, or with a foreign power[.]” This wording is important because the Constitution does not so much authorize states to enter into Compacts as it bars states from entering into Compacts without congressional consent. Unlike the Articles of Confederation, however, in which interstate disputes concluded by appeal to Congress, the Constitution vests ultimate resolution of interstate disputes in the Supreme Court either under its original jurisdiction or through the appellate process. For a thorough discussion on the history of interstate Compacts from their origins to the present, see generally, Michael L. Buenger & Richard L. Masters, The Interstate Compact on Adult Offender Supervision: Using Old Tools to Solve New Problems, 9 Roger Williams U. L. Rev. 71 (2003); Felix Frankfurter & James M. Landis, The Compact Clause of the Constitution – A Study in Interstate Adjustments, 34 Yale L.J. 685 (1925); Michael L. Buenger, Jeffrey B. Litwak, Michael H. McCabe & Richard L. Masters, The Evolving Law and Use of Interstate Compacts 2d ed. (ABA Publ’g 2016).