Full Faith and Credit Clause

Article IV, Section 1 of the United States Constitution, known as the "Full Faith and Credit Clause", addresses the duties that states within the United States have to respect the "public acts, records, and judicial proceedings of every other state." According to the Supreme Court, there is a difference between the credit owed to laws (i.e. legislative measures and common law) as compared to the credit owed to judgments. Judgments are generally entitled to greater respect than laws, in other states. At present, it is widely agreed that this Clause of the Constitution has little impact on a court's choice of law decision, although this Clause of the Constitution was once interpreted differently.

Article IV, Section 1:

Full Faith and Credit shall be given in each State to the public Acts, Records, and judicial Proceedings of every other State. And the Congress may by general Laws prescribe the Manner in which such Acts, Records and Proceedings shall be proved, and the Effect thereof.

A similar clause existed in Article IV of the Articles of Confederation, the predecessor to the U.S. Constitution: "Full faith and credit shall be given in each of these States to the records, acts, and judicial proceedings of the courts and magistrates of every other State." A Pennsylvania court explained in 1786 that this provision in the Articles of Confederation did not direct that "executions might issue in one state upon the judgments given in another", but rather was "chiefly intended to oblige each state to receive the records of another as full evidence of such acts and judicial proceedings."

At the Philadelphia Convention, James Madison said that he wanted to supplement that provision in the Articles of Confederation, to let Congress "provide for the execution of Judgments in other States, under such regulations as might be expedient." By September 1, 1787, negotiations at the Constitutional Convention had led to the following draft which included supplementary language as Madison had requested:

Full faith and credit ought to be given in each state to the public acts, records, and judicial proceedings, of every other state; and the legislature shall, by general laws, prescribe the manner in which such acts, records, and proceedings, shall be proved, and the effect which judgments, obtained in one state, shall have in another.

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