An important procedural note is that the two year statute of limitations in medical malpractice cases begins when the "plaintiff actually knew, or in the exercise of reasonable diligence should have known, the cause and existence of his injury." Wehrman v. U.S., 830 F.2d 1480, 1483 (8th Cir. 1987). This differs from the "time of injury" specification for other damages under the FTCA. Hence, the injured person is not penalized for not immediately realizing his injury. Only after a plaintiff knows or should know that he has been injured and who has inflicted the injury does the clock start to run. That said, the plaintiff does have a duty to investigate the unknown cause of the known injury. Osborn v. United States, 918 F.2d 724, 732 (8th Cir. 1990).

The scope of the FTCA is that "the United States shall be liable, respecting the provisions of the United States Code relating to tort claims, in the same manner and to the same extent as a private individual under like circumstances." However, the FTCA contains certain exceptions, notably the discretionary function exception and the assault and battery exception. Therefore, in cases of alleged medical malpractice, such as the care and treatment of patients in government hospitals, the federal government often asserts either of these exceptions as an affirmative defense to liability. The results have been mixed.