A Research on the Proportion of Mental Defectives among Delinquents

Abstract

A careful study of the proportion of mental defectives among delinquents is extremely timely. There exists a great discrepancy between the general opinion of thoughtful and experienced observers, such as judges, probation officers and teachers, on the one hand, and statements made by some experimental workers on the other. The percentage of feeble-minded among offenders, according to these statements, has ranged even as high as 89 per cent. Teachers who know the large number of delinquents who can do, and have done in their class rooms, 7th and 8th grade, and even high school work, express themselves as greatly surprised at these extraordinary figures. Now, in all studies of offenders, we must recognize at once the fact that we are dealing with a selected group. For, of course, such investigations can take into account only the caught offender. Those who, because of unusual cleverness or because of fortunate circumstances escape detection and arrest, may be equally or more culpable than those apprehended. Though intelligence is not the only factor responsible for the lack of detection and arrest, yet it is undoubtedly a large one. This means that in all studies of offenders, there is a selective force operating which tends to eliminate the brightest and most capable. Nor is this all; for the majority of such data as have appeared have been based upon the study of those in institutions-in reformatories and state industrial schools. When this is true we have not merely a selected group, but rather a selected portion of an already selected group. For now-a-days there is a tendency to commit to institutions only the most incorrigible or the least hopeful offenders. With our present sybtlem, all those believed capable of reformation under probation are given this opportunity. In consequence we should expect to find a lgrger percentage of the dull and incapable among those sent to reform and state schools than among those released on parole. These facts necessarily influence in a large measure the results of investigations and give a picture that is distorted if applied generally. The results should be interpreted as showing conditions that exist among the group investigated only. Unfortunately, only too often the data are quoted as if representative of offenders in general. If 25 per cent of the inmates of reformatory institutions are found to be mentally defective,