|Notably used to avoid the charge that the Iraq war is illegal, so something of a carte blanche for US government employees whom the legal system wishes to defend.
The Federal Employees Liability Reform and Tort Compensation Act of 1988, (Westfall Act), 28 U.S.C. § 2679, amended the Federal Tort Claims Act to provide for the substitution of the United States as a defendant in any action where one of its employees is sued for damages as a result of an alleged common law tort committed by the employee within the scope of his or her employment.
The United States Supreme Court's decision in Westfall v. Erwin, 484 U.S. 292 (1988) limited a federal official's absolute immunity from tort claims to situations where the official's actions were "within the outer perimeter of an official's duties and . . . discretionary in nature." The US Congress saw this as an erosion of the common law tort immunity formerly available to federal employees and so the Westfall Act "was rushed into law in 1988 to avoid what was expected to be a crisis in exposing federal workers to court suits".
The United States Department of Justice cited this act in the case of Saleh v. Bush, avoiding the need to rule on whether the Iraq War was a premeditated war of aggression, by claiming that the court had no "subject-matter jurisdiction" since George Bush et al. were "Government employees [acting] in the scope of their employment". A 2016 appeal was rejected in February 2017 by 3-0, with Judge Susan Graber stating that "What took place in the late 1990s was not planning, but only advocacy."