From mad-doctor to forensic witness: The evolution of early english court psychiatry

Abstract

When nine medical witnesses offered testimony in the 1843 trial of Daniel McNaughtan, few observers in the courtroom could have appreciated the evolutionary dynamics which were transforming the mad-doctor into an expert witness. Certainly, medical witnesses were no strangers to the court; one can find written acknowledgement of medical testimony in continental jurisprudence dated as early as 13 11. The growth of legal medicine was encouraged in France through the use of surgeons as court experts as evidenced by Norman laws and decrees of St. Louis, and in Italy by the Canon Law which mandated that the “character of wounds . . . be determined by medical experts.“’ Cases involving impotency, leprosy, and deaths of a suspicious nature all contributed to the growth of and reliance on medical pronouncements. Forensic medicine until the early 19th century was largely confined to injuries and diseases of a physical nature. What was novel by the 1840s in Britain was the dramatic increase in the participation of medical witnesses in trials in which they had heretofore played but a small role. Where mad-doctors appeared in only 1 in 10 insanity trials in 1760, by 1840 they testified in half of all insanity cases concerned with a property offense, and almost 90% of trials involving personal assault. Clearly, the mad-doctor had “arrived” by the mid 19th century in England, but one wonders what avenue these new medical witnesses had taken to claim legitimacy for their expertise. This article reports on a study of insanity trials heard in Britain between 1760 and 1843 which was undertaken to determine, among other matters: (1) who the first medical witnesses were, (2) how they became acquainted with criminal defendants and found their way into the courtroom, and (3) in what manner the court responded to their increasing presence. In sketching the contours of the professional association among the first forensic specialists in insanity, we are also asking a more fundamental question: to what extent did these early medical witnesses