According to the Connecticut General Assembly`s Office of Legislative Research, the Political Consent Compact Clause Theory is the standard on which the Supreme Court bases its decisions on intergovernmental compacts. The crux of this argument is that the determination "whether the pact contains a political matter that affects the interests of the Alliance or the interests of the uns condensed sister states, in which case congressional approval is required," is the only basis on which the constitutionality of such agreements lies. The United States Steel Corp. v. Multistate Tax Commission in 1978 held that the number of states participating in an agreement "is irrelevant if it does not unduly strengthen state power to the detriment of federal supremacy, and the powers conferred on the administrative body must also be assessed with a view to such improvement."   Compacts` approaches to their management are different. Pacts that get congressional approval will become federal law. Covenants, as treaties between States, affect the rights and obligations of States parties (and their citizens); The U.S. Supreme Court has emphasized that the interests of non-partisan states could be a factor in deciding whether or not to approve Congress. A covenant usually contains provisions relating to its subject matter; the specific conditions relating to the subject matter of the Pact; in some cases, the establishment of an intergovernmental agency to manage the pact or any other management method; sources of funding; and other contractual terms, such as dispute settlement, enforcement, termination of the covenant or withdrawal of a member. Many examples of pacts and intergovernmental authorities set up to manage them are available online.
As a treaty, an intergovernmental covenant primarily concerns the rights and obligations of States that have decided to become contracting parties and their respective citizens, since the covenant is adopted as law by their respective legislators. However, some covenants go so far as to look specifically at the impact (if any) of these covenants on States that are not contracting parties. A covenant may contain provisions to the end that the covenant does not affect other agreements concluded by the parties with States not parties.  A pact can also define how non-condensed states can participate in activities related to the pact.  For example, the Interstate Pest Control Compact (which is no longer in force) provided that the Compact`s board of directors or its executive committee could not spend funds from an insurance fund established by the Covenant in an uns condensed state, unless justified by the conditions in that state and the benefits to the Covenant parties – and could impose conditions for such expenses.  Under international law, a treaty is any legally binding agreement between states (countries). . . .