From heritage,org.
The Unconstitutionality of the NPV: Compact Clause
Supporters of the NPV claim that because the Constitution gives state legislatures the power to determine how electors are chosen, the NPV is constitutional and requires no approval by Congress. Such claims, however, are specious.
The NPV is unconstitutional because it would give a group of states with a majority of electoral votes “the power to overturn the explicit decision of the Framers against direct election. Since that power does not conform to the constitutional means of changing the original decisions of the framers, NPV could not be a legitimate innovation.”
[17]
The Constitution’s Compact Clause provides that “No State shall, without the Consent of Congress…enter into any Agreement or Compact with another State.”[18] The Founders created the Compact Clause because they feared that compacting states would threaten the supremacy of the federal government in matters of foreign affairs and relations among the states.
[19] If states could make agreements among themselves, they could damage the nation’s federalist structure. Populist states, for example, cannot agree to have their U.S. Senators vote to seat only one Senator from a less populous state.
The very purpose of this clause was to prevent a handful of states from combining to overturn an essential part of the constitutional design. The plain text makes it clear that all such state compacts must be approved by Congress.
By circumventing the checks and balances of Congress, the NPV would risk setting a precedent that states can validate non–congressionally approved compacts as a substitute for a constitutional amendment. Undoubtedly, many liberal activist groups would like to create their own compacts or to lobby states individually to join compacts. Such compacts could then create
de facto constitutional amendments regarding many different public policy issues—including purely federal matters.
Even though the plain text of the Constitution makes it clear that no compact shall be made by states without the consent of Congress, courts have recognized certain narrow agreements as exceptions to the limitations of the Compact Clause.
[20] Interstate compacts that governed boundary disputes between states were almost always upheld as valid.
[21] Although states sometimes did submit their compacts to Congress for ratification, there has been an implied understanding that interstate agreements were legitimate as long as they had a limited, specifically local impact and did not affect national prerogatives.
In the 1920s, interstate compacts expanded their scope and began to establish regulatory agencies.
[22]As the 20th century progressed, compacts were increasingly used to tackle broader issues facing the states. Modern interstate compacts can govern everything from environmental issues to water conservation, waste disposal, education, child welfare, crime control, and others—if approved by Congress.
[23]
Although some of the interstate compacts have expanded to include more national issues, none would affect the federal government or non-participating states to the extent that the NPV does. The NPV addresses an area of national concern by effectively abolishing the Electoral College and changing the method of choosing the President. However, unlike other agreements that are exempt from the requirement of congressional approval, the NPV aims to control the behavior of compacting and non-compacting states alike and “harms those states whose citizens benefit from the current system of election.”
[24]
Should the NPV movement reach its target of 270 electoral votes, states not involved in the compact will have been co-opted into an electoral regime despite having never consented to the compact. This distinction delineates this compact from others, which have dealt with even arguably national issues.