Article IV of the U.S. Constitution is sometimes called the “States’ Relations Article.” ALDF_00001751 It contains several provisions concerning the federalist structure of government established by the Constitution, which divides sovereignty between the states and the National Government.ALDF_00001752

Sections 1 and 2 concern the states’ relationships with each other. Section 1 is referred to as the Full Faith and Credit Clause, and requires states to recognize the public acts, records, and judicial proceedings of other states;ALDF_00001753 for example, states must generally give effect to judgments issued by an out-of-state court.ALDF_00001754 Section 2 addresses interstate comity, that is, harmony and cooperation among the states. Its first clause grants the citizens of each state the privileges and immunities of the citizens of other states, preventing states from discriminating against non-residents in favor of their own citizens.ALDF_00001755 Its second clause addresses when a person accused of a crime flees from one state to another, requiring the state where the fugitive is found to return him to the state where he has been charged with a crime, upon proper demand.ALDF_00001756

Sections 3 and 4 concern the states’ relationships to the National Government. Section 3 grants Congress two important powers: to admit new states into the union,ALDF_00001757 and to govern federal territories and property.ALDF_00001758 Through Section 4, known as the Guarantee Clause, the United States promises to protect the states against foreign invasion and domestic insurrection, and to ensure that each state has “a Republican Form of Government.” ALDF_00001759