Article Four of the United States Constitution

Article Four of the United States Constitution outlines the relationship between each state and the others, and the several States and the federal government.

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.

The first section requires states to extend "full faith and credit" to the public acts, records and court proceedings of other states. Congress may regulate the manner in which proof of such acts, records or proceedings may be admitted.

In Mills v. Duryee, 1t1 U.S. (7 Cranch) 481 (1813), the United States Supreme Court ruled that the merits of a case, as settled by courts of one state, must be recognized by the courts of other states; state courts may not reopen cases which have been conclusively decided by the courts of another state. Later, Chief Justice John Marshall suggested that the judgment of one state court must be recognized by other states' courts as final. However, in McElmoyle v. Cohen, 38 U.S. (13 Pet.) 312 (1839), the court heard a case where one party obtained a judgment in South Carolina and sought to enforce it in Georgia, which had a statute of limitations that barred actions on judgments after a certain amount of time had passed since the judgment was entered. The court upheld Georgia's refusal to enforce the South Carolina judgment. The court found that out-of-state judgments are subject to the procedural law of the states where they are enforced, notwithstanding any priority accorded in the states in which they are issued.

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