Article I, Section 10, Clause 3 of the United States Constitution
Article 1, Section 10, Clause 3
3: No State shall, without the Consent of Congress, lay any Duty of Tonnage, keep Troops, or Ships of War in time of Peace, enter into any Agreement or Compact with another State, or with a foreign Power, or engage in War, unless actually invaded, or in such imminent Danger as will not admit of delay.
The Founders understood that the federal government can threaten individual liberty, but so can the state governments. The Constitution recognizes threats from both actors and, therefore, contains specific limitations on both. Article 1, Section 9 limits the federal government; Article 1, Section 10 limits state governments.
Section 10 consists of absolute prohibitions on the states (e.g., prohibitions relating to military and monetary powers) and qualified prohibitions on the states (i.e., prohibitions that Congress may suspend).
Section 10, Clause 3 contains qualified prohibitions on a variety of activities. The prohibition on states charging duties of tonnage prevents state-specific protectionism and protects Congress’s commerce power. Because standing armies were a grave threat to the new republic, the constitution prohibits them at the state level. States may maintain militias, but not standing armies. But, the most significant portion of the clause concerns the ability of states to enter into agreements with foreign nations or other states. As Michael S. Greve notes in Compacts, Cartels and Congressional Consent, “For a federal republic, and especially for a nascent federal republic, the prospect of separate, unsupervised agreements among its member-states and between a member-state and a foreign nation must constitute a cause for alarm.”
The Articles of Confederation forbade the states from entering into an agreement with foreign powers. Additionally, any “treaty, confederation, or alliance whatever” among the states required congressional consent, and Congress would settle any disputes arising between the states. But the Articles of Confederation proved ineffective. The Constitution supplied a remedy. The Constitution created a new apparatus for the federal government to engage foreign nations: the president would be the chief actor in foreign affairs. He would negotiate treaties and, in turn, the Senate had to ratify treaties before they went into effect. Individual states could not enter into agreements or treaties with foreign nations. But, in the event of foreign invasion, an individual state could respond.
Agreements between the states pose threats to federal powers, to states not party to the agreement, and even to individual rights. By requiring such agreements to have the consent of Congress, other states would be informed of the agreement and able to protect their interests and the rights of their citizens. In many ways, congressional approval on state compacts was a compromise. James Madison wanted to give the federal government a much broader power over the state governments: specifically, he advocated a congressional negative on state laws. Delegates at the Convention compacts clause rejected Madison’s proposal—three times—as overly nationalist and unnecessarily broad. The Convention instead opted for federal supremacy over certain categories of activity, blanket prohibition of some activity, and congressional approval for any agreement between the states. Together these prohibitions mollified Madison’s concerns and protected against state governments’ encroachments on liberty.
Though the Compacts Clause makes clear that forming compacts is prohibited without the consent of Congress, it is not clear what form that consent must take. Does it require a law be passed and signed by the president? Or can Congress accomplish it without presentment? Nor does the clause specify whether Congress must consent prior to the formation of the compact. There is also debate about the scope of these compacts. Compacts prior to 1921 primarily concerned boundary disputes. Compacts in the later 20th century include complex regulatory schemes that may present separate constitutional problems. These ambiguities will likely be tested as states become more creative with the scope and substance of their agreements.
Julia Shaw is the Research Associate and Program Manager at the B. Kenneth Simon Center for American Studies, The Heritage Foundation.
 Michael S. Greve, Compacts, Cartels, and Congressional Consent, 68 M.L.Rev. 285, 296 (2003).
How often does Congress effectively impose a defacto negative on state laws by passing unconstitutional regulation? Right now there is a lot of nationalization measures coming out of Congress for what are not granted powers by the states.
“James Madison wanted to give the federal government a much broader power over the state governments: specifically, he advocated a congressional negative on state laws…Delegates at the Convention compacts clause rejected Madison’s proposal—three times—as overly nationalist and unnecessarily broad.”
Later, in Article III we learn two keys things there that corresponds to the powers of the federal government:
1) Congress regulates the federal court system including how it is structured and what is the appellete court jurisdiction.
2) The courts are granted the role of playing the arbiter among disputes between states.
The power of arbitration implies a negative upon to nationalization power at any whim of Congress. An example of arbitration power working in conjuction with the Compacts Clause in affecting the behavior of states is desire of the states to keep the federal government from meddling in predominately internal affairs by way of managing waterways and aquifiers. Since waterways and water sources can cross state boundaries, western states have erected in concert their own water cooperative water management projects by the consent of Congress to keep such issues from landing in federal arbitration court AND to keep Congress from intervening with more regulatory law such as from the EPA, et.al.
Constitutionally, the federal arbitration power is actually one of the most powerful tools in the federal tool box that goes unsung; largely because there is such gross misstep in the passing of unconstitutional law. If the Congress truly kept fast to keeping within the binds of the Enumerated Powers, then the power of regulating the courts would weigh in more on arbitration. This then would become a defacto nationalization of common arbitration law. Why? Because there is such a thing as “binding arbitration” where the arbiter lays down ground rules for arbitration and, if there is an impasse, to actually lay down what the settlement parameters are going to be. So if Congress, in its duties of controlling costs and regulating the courts found, say, there are on average 200 waterway disputes among the states, may then set summary rules for binding arbitration that the courts follow. This then would send a signal to the states that, if there is a dispute among state, what the likely outcome will be if such issues land in arbitration court. So state behavior would entertain more cooperative compacts among states that Congress would then approve to avoid courts knowing what courts likely will decide.
Getting Congressional approval for cooperative Compacts ought to be construed to be in force when Congress approves it. It is best that states draw the compacts themselves as preferred to lawsuits.
Another tid-bit on State Compacts vs. Arbitration is that Arbitration Law is a law passed by Congress; where State Compacts are a mere approval of Congress no more than that of Congress passing a Resolution that the President does not sign. When the Articles of Confederation (AoC) were in force, there was no President at all for signing bills. But the Constitution only weighs on the signing of bills into laws by the President. As State Compacts are not law, and the AoC had the practice of not requiring a signature of a president since there was no president, [note that the delegates under the AoC acted also as the executive power/branch in those days] then the practice ought to be continued under this constitution. This is because a State Compact, which is not a law, would then be preferred to avoid the Congress from making a more fixed, common arbitration law that is signed by the President. Once that common arbitration law is approved, it would become a barrier to states to gain a different settlement outcome. So for states to retain more liberty and autonomy their behavior ought to prefer making State Compacts, even if it means the making of a cooperative that is structured in such a way that arbitration law may actually mandated a different structure if the matter went to court.
And all these measures taken in tandem, the Compacts Clause, and the Arbitration Power clause covered later are absolutely constitutional measures of governance.