 Sovereign immunity, according to the Supreme Court in "Hans v. Louisiana" (1890), normally prevents a state from being sued by its own citizens in federal court.This bar against suit, the Court said, came from the Eleventh Amendment, even though the express terms of that amendment provide only that citizens of one state cannot sue another state.In "Fitzpatrick v. Bitzer" (1976), however, the Court made an exception to that usual rule.