Since its debut in the psychiatric nomenclature in 1980, post-traumatic stress disorder (PTSD) has had a dramatic impact on criminal and civil jurisprudence. PTSD has created a cottage industry among both criminal and negligence attorneys and mental health practitioners. The diagnosis first achieved public notoriety when it was introduced as a new basis for the insanity defense. More recently "syndrome evidence" of the subtypes and variations of PTSD have encroached on the substantive criminal law of self-defense. In addition, the diagnosis may have an impact on such traditionally legal and factual determinations as the credibility of witnesses and may undermine conservative tort doctrine that attempts to cabin psychic injury. The emerging legal area of victims' rights has been strengthened and paradoxically divided by PTSD. Yet the newly defined disorder of PTSD has not borne such a heavy forensic burden easily. Indeed the diagnosis poses for psychiatry some of the very problems it supposedly solves for legal purposes, including the illusory objectivity of the causative traumatic event and the expert's dependence upon the victim's subjective and unverifiable reports of symptomatology for the diagnosis.