A narrow definition of insanity opined by medical experts in the oliver smith will case in 1847

Physicians specializing in the diagnosis and treatment of insane people (alienists) emerged in the early 19th century and offered their expertise for the courts to consider in judgments of mental competence. In the Oliver Smith will case (1847), the competency of an attesting witness was contested on the issue of insanity. Four well-known alienists testified at trial. Although the insanity of the witness could have been viewed in broader terms, the experts used a narrow definition of insanity based primarily on the presence of delusions. These opinions were only partially consistent with contemporaneous medical notions of insanity and the broad definition of criminal responsibility. We suggest three explanatory factors for the narrow definition related to available medical knowledge, courtroom restrictions including the case itself, and mid-19thcentury relationships between mental medicine and the law.