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.
The rule of 28 U.S.C. §§ 1738-1739 pertains not merely to recognition by state courts of the records and judicial proceedings of courts of sister states but to recognition by
every court within the United States, including recognition of the records and proceedings of the courts of any territory or any country subject to the jurisdiction of the United States. The federal courts are bound to give to the judgments of the state courts the same faith and credit that the courts of one state are bound to give to the judgments of the courts of her sister states. 1 Where suits to enforce the laws of one state are entertained in courts of another on principles of comity, federal district courts sitting in that state may entertain them and should, if they do not infringe federal law or policy. 2 However, the refusal of a territorial court in Hawaii, which had jurisdiction of the action on a policy issued by a New York insurance company, to admit evidence that an administrator had been appointed and a suit brought by him on a bond in the federal court in New York in which no judgment had been entered, did not violate this clause. 3
The power to prescribe the effect to be given to the judicial proceedings of the courts of the United States is conferred by other provisions of the Constitution, such as those that declare the extent of the judicial power of the United States, which authorize all legislation necessary and proper for executing the powers vested by the Constitution in the Government of the United States, and which declare the supremacy of the authority of the National Government within the limits of the Constitution. As part of its general authority, the power to give effect to the judgment of its courts is coextensive with its territorial jurisdiction. 4