The Full Faith and Credit Clause is the familiar name used to refer to Article IV, Section 1 of the United States Constitution, which addresses the duties that states within the United States have to respect the records and judicial proceedings of every other court.
The contradictions between the decisions of two courts have created many problems whereas Full Faith and Credit shall be given. The evidence and the facts established by the Family Court shall not be proved once again. The facts established by the Family Court during the trial are binding for any other court.
In 1804, Congress enacted statute requiring that full faith and credit be given to the records and judicial proceedings of the territories of the United States.
The Supreme Court held in Mills v. Duryee (1813) and Hampton v. McConnell (1818) that a judgment rendered in one court has conclusive effect in other court. The court in the original state must have had jurisdiction, and the requirements of due process must have been satisfied. Also, the original judgment must have been on the merits and it must have been final.
The Supreme Court held in Stoll v. Gottlieb (1938) and St. John v. Wisconsin Employment Relations Board (1951) that federal courts must grant full faith and credit to state court judgments, and vice versa.