An amendment is an improvement, correction or revision of the original content of the Constitution approved in 1788.
The authority to amend the U.S. Constitution is derived from the Artice V of the Constitution. After the Congress porposes an amendment the Archivist of the United States who heads the National Archives and Records Administration (NARA) is in charge of administrate the ratification process.
The first step to amending the constitution is to receive a proposal for it and the Constitution foresee two ways; a proposal made by the Congress with two thirds of majority votes in both House of Representatives and the Senate or, the ohter way, a constitutional convention called for by two thirds of the States Legislatures. It is untill these days that neither of the 27 amendments were proposed by constitutional convention.
When the Congress propose an amendment it does in the way of a joint resolution, this resolution does not go to the White House for aproval because the president don´t hold a constitutional role. It goes directly to the NARA to be publish. In there the Office of the Federal Register (OFR) is the one in charge to do this and it also adds legislative history notes to the joint resolution before publishing as a slip law.
After the OFR prepare the joint resolution is the Archivist of the United States who have to submit the proposed amendment to the States for their consideration by sending a letter to the governors; then is in the hands of the governors to present the amendment to their respectives States legislatures or to call a convention depending what the Congress sepecifies. If the State ratifies the amendment it should send back to the Archivist an original or certified copy of the State action to be examine by the OFR to declare it legal and authentic and hold it untill the amendment is adopted or fails.
The amendment is adopted when three fourths of the States legislatures aprobed it and this way become a part of the Constitution.
So we can infer from this little summary that the first step to amend the constitution is to present a proposal either by the Congress with two thirds of the votes from the House and the senate or by a constitutional convention called by two thirds of the States legislatures.
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