Thompson v. Thompson

The Parental Kidnapping Prevention Act (PKPA) extended full faith and credit to child-custody orders, barring simultaneous jurisdiction once one state exercises it; Susan Clay (defendant) initially obtained joint custody of her son Matthew in California, then sole custody pending further investigation after moving to Louisiana, then obtained a Louisiana judgment enforcing and finalizing that sole custody. Two months later, California's completed investigation instead awarded sole custody to David Thompson (plaintiff), who then sued in federal district court in California seeking a declaration that the Louisiana ruling was invalid and California's was valid; the district court dismissed for lack of jurisdiction, the Ninth Circuit affirmed, and Thompson appealed.