The legal requirements for compensable injury in civil law gradually has loosened over the years from the physical effects of direct injury to include the emotional effects of direct injury, the emotional effects of witnessing injury to others, the emotional effects of knowing of injury to others, and a person's fear that he or she may become ill at a later date. Although a psychiatric diagnosis is not required to bring action, post-traumatic stress disorder (PTSD) has become the favored diagnosis in cases of emotional distress. Also, in criminal law, defenses based on PTSD have become increasingly common, being used as the standard defense in selected situations. The limits of the use of PTSD as a defense remain to be clarified; differing judgments have been made in similar cases by different courts.