This paper deals with the relation between crime and the psychoses complicating pellagra, and is based on a study of the cases of accused persons suspected of being insane, and admitted to the Abbasia Mental Hospital for mental examination and report during eight years from 1941 to 1948 inclusive. This examination was, in the great majority of the cases, carried out by the writer who, in virtue of his official position, is the expert psychiatrist to the Office of the Procureur-General.