Nature versus nurture. There has been much controversy among psychologists and sociologists in the late 20th century concerning whether some people are genetically disposed to crime or whether illegal acts have their origin in one’s upbringing and environment. There is evidence to support both views. Those who believe it probable that there is a genetic disposition to crime have noted certain physical and personality differences between delinquents and non-delinquents. Delinquents have been found to have sturdier bodies and to act in a more aggressive way than non-delinquents. In their personality traits, delinquents are more extroverted, narcissistic, and impulsive, and less able to delay the satisfaction of desires. Some psychologists believe that there is an inherited flaw in the genetic make-up of a criminal that leads to rejection of society’s standards. Others note that many violent prisoners have higher than normal levels of the male sex hormone testosterone.
The contrary opinion tends to view delinquents as not substantially different from the remainder of the population. Not all sturdily built individuals, for instance, become criminals; many make their living as athletes or in a variety of professions. Studies in Great Britain have shown that delinquents tend to come from families where there is tension and much difficulty in interpersonal relationships. Family breakdown is also found to be a significant factor. The United States Bureau of Justice Statistics reports that in the late 1980s, about 70 per cent of the juveniles in state reform institutions grew up in single parent (usually with the mother as head of household) or no-parent families.
