For as long as medicine has sought to diagnose and treat pathologies of thought, feeling, and behavior, society has turned to mental health professionals for insights into the perennial problems of crime and violence. The modern subspecialty of forensic psychiatry was pioneered in the United States by Dr. Isaac Ray, whose influential 1838 Treatise on the Medical Jurisprudence of Insanity argued for reform of the insanity defense based on advances in medical understanding of mental illness.1 Today, as discoveries in clinical neuroscience have fostered the increasing integration of neurology and psychiatry in the diagnosis and treatment of mental illness, improved understanding of brain structural-functional relationships has also begun to influence the ways in which the criminal justice system views antisocial behavior. In the 2005 landmark case of Roper v. Simmons, for example, the U.S. Supreme Court ruled that capital punishment for crimes committed under the age of 18 is unconstitutional, based in part on advances in research concerning adolescent cognition and brain development.2
Neuropsychiatry can be viewed as a clinical approach to the patient that seeks to assess and treat psychopathology based on knowledge of structural-functional connections in the brain and of the clinical phenomenology of central nervous system disorders. When confronted with a pathological change in mental status or behavior, neuropsychiatry asks what might be called the classical neurological question: Could this be a disorder of the nervous system and, if so, where is the lesion? Forensic psychiatry is a psychiatric subspecialty that comprises two major domains of practice. First, as clinicians trained to work in secure hospitals and correctional settings, forensic psychiatrists have expertise in the care and treatment of patients involved with the criminal justice system. Second, as consultants and expert witnesses, forensic psychiatrists provide medical-legal opinions regarding mental health issues raised in the courts. Forensic neuropsychiatry, then, can be described as the application of a clinically integrated psychiatric and neurological approach to the care of patients in forensic mental health settings and to the performance of forensic psychiatric evaluations for the courts.
Neuropsychiatric and comorbid neurological conditions, ranging from neurodevelopmental disorders (NDDs), to sequelae of head injury, to neurodegenerative dementias, are highly prevalent in forensic mental health settings.3–5 For clinicians practicing in prisons, jails, and forensic psychiatric hospitals, knowledge of the presentation and workup of neuropsychiatric disorders can prove invaluable, especially because correctional and other public-sector facilities often lack routine access to neurological consultation, neuroimaging, and other neurodiagnostic testing. Psychiatrists performing evaluations in the courts can expect to encounter criminal defendants or civil litigants presenting with conditions reflecting the full range of neuropathology. The ability to recognize the clinical manifestations of neuropsychiatric disorders and assess their relevance to medicolegal issues before the courts, therefore, can be essential to formulating and communicating accurate and useful expert opinions.
The evaluation of criminal and civil competencies, such as competence to stand trial or the need for guardianship, ...