Congenital determinants of violence.

Specialization--the predisposition to violent behavior persisting over an extended period of time--is considered in relation to congenital factors, to determine whether such factors are contributory to this predisposition. Congenital factors include inherited characteristics and perinatal experiences. Evidence for inherited characteristics in criminal behavior is approached through family studies, the study of twins, and adoption studies. Of those three, adoption studies provide the most fertile ground for study. Predisposition toward criminal behavior is noted to be limited to property crime. The second congenital factor is the perinatal experience. Minor physical anomalies appear to be strongly related to hyperactivity and later criminal involvement, but only if the offender was reared in an unstable, nonintact family. Indices of perinatal problems relate to later violent crime, rather than to property crime, and may have as their basis some form of trauma occurring very early in life.