An early draft of the Constitution permitted amendments to be proposed and adopted only by interstate convention.1) Then the Framers added provisions allowing Congress to propose amendments and requiring state ratification.2) Congress received the power to propose because the Framers believed that Congress's position would enable it readily to see defects in the system.
However, some delegates—notably George Mason of Virginia—pointed out that Congress might become abusive or exceed its powers.3) It might therefore refuse to adopt a necessary or desirable amendment, particularly one designed to curb its own authority. Accordingly, the Framers added the convention for proposing amendments as a vehicle for the states to present corrective amendments for ratification while bypassing Congress.4)
The purpose of the convention as a “congressional bypass” was much discussed during the debates over the ratification of the Constitution. Illustrative was the comment of Samuel Rose, a New York state legislator who supported the Constitution at his state's ratifying convention:
The reason why there are two modes of obtaining amendments prescribed by the constitution I suppose to be this—it could not be known to the framers of the constitution, whether there was too much power given by it or too little; they therefore prescribed a mode by which Congress might procure more, if in the operation of the government it was found necessary; and they prescribed for the states a mode of restraining the powers of government, if upon trial it should be found that they had given too much.5)
James Madison stated it more succinctly in The Federalist No. 43: The Constitution “equally enables the General, and the State Governments, to originate the amendment of errors, as they may be pointed out by the experience on one side or on the other.”