Criminal intelligence

Abstract

Reviews the books, Criminal intelligence by Carl Murchison; and Psychological and educational survey of 1916 prisoners in the Western Penitentiary of Pennsylvania by William T. Root. These two recent studies of prison populations raise anew the issue of the validity and meaning of tests of adult intelligence and make emphatic the need of further analysis and standardization. Murchison using the Army Alpha concludes that convicted criminals as a body are equal or superior to the general population. Root employing the Stanford-Binet individual examination finds his prison group to rank very low in intelligence. Murchison classifies the long list of legal crimes into seven groups, the point of view of the classification being legal and logical rather than psychological; certain of the groups would appear to be very heterogeneous, as for instance the one called "crimes of physical injury," within which both murder and arson are included. Intelligence scores varied decidedly with the type of crime, those convicted of crimes of deception and fraud standing highest and those convicted of sex crimes lowest. The distribution of the various crimes among the prisoners showed racial-national variations. Root's paper is a compact presentation of the results of an intensive study of 1916 prisoners made with the aid of the prison psychiatrist and of graduate students so that from eight to twelve hours of individual case work were done on each man. Root's findings are similar to Murchison's in point of the existence of wide variations in intelligence with type of crime, race and age; they also reveal a preponderance among his prisoners of very youthful men. (PsycInfo Database Record (c) 2025 APA, all rights reserved)