When Wilson and Herrnstein's "Crime and Human Nature" first appeared in 1985, it caused a major debate. American sociologists had generally ascribed crime to environmental factors, particularly poverty. Wilson and Herrnstein proposed that constitutional factors, coupled with poor parenting, were really the causes of crime. It was the first major examination of such factors since the early days of criminology. The authors proposed that the following constitutional factors predisposed an individual to crime:
1) Mesomorphic body type: There are three body types and mesomorphs are described as heavily built, either muscular or fat, and shorter than average. The authors don't even attempt to explain why this would predispose an individual to crime. But the statistics they use to back up this claim can't really be denied. Criminals are overwhelmingly mesomorphs with a slight emphasis to endomorphism (roundness) rather than ectomorphism (lean build). Stereotypes of criminals back up this claim: Think of the way famous mafiosos are built: John Gotti, Sammy Gravano, Tony Soprano, etc. Realizing that they can't explain why this affects crime, the authors simply state that it shows that constitutional factors matter; The other biological factors they describe are more straightforward.
2) Age: Criminals are predominantly young. Crime peaks from ages 16-25 and begins to descend downwards from thereon, although violent crime peaks from ages 24-28. Unlike body type, the authors seem to think they know why age causes crime, offering several possibilities. Young people have shorter time horizons, and are more interested in immediate gratification. Young people are less well off financially, have less dependents and so on. Few people would dispute age as a major factor in crime.
3) Sex: Men commit far more crimes than women, although the figures aren't completely clear as to how much more. An estimation of 90 percent seems likely. The question is why? Obviously men are more aggressive than women, but why do women commit crimes? The authors state that women commit crimes for the same reasons as men. As for why, all they can say is that for reasons both nature and nurture, men have different sex roles than women, and these affect crime.
4) Intelligence: Low intelligence, particularly the verbal component, seems to have a major impact on the criminal individual. The reasons are that those with low intelligence discount future events as being too far off to matter. They try and live for the moment. They may also be less able to grasp moral concepts.
5) Personality: Criminals differ on personality in nearly every study done on them. Criminals tend to be more aggressive, unafraid, assertive, impulsive and extroverted than others. They are also poorly socialized, meaning they display little regards for others feelings.
The authors are quick to note that constitutional factors are not only hereditary. They may also be affected by poor pre-natel care. Thus the genes alone don't dictate criminal behavior, but they do predispose an individual to crime. If those traits are reinforced by certain environmental factors, then criminal behavior may result.
By far the most important developmental factor, according to the authors, is parental style. Inconsistent and random discipline prevents a child from knowing when to expect punishment. The rules are not made clear, and the child never internalizes them. Furthermore, a cold parent does not produce the necessary attachment with their child that is important in later development. The child never develops a desire to please the parent or obey the rules. This pattern continues into adulthood. As far as developmental and environmental factors go, this is really the only one the authors point to as having a major impact. Indeed, they spend the next few chapters explaining why other factors don't matter, including schools, neighborhoods, labor markets, and television violence. Delinquents are likely to flock together in the schoolyard: A few rotten boys don't spoil the others. Certain kinds of neighborhoods attract certain kinds of people, and they point to an ecological fallacy: Ascribing the characteristics of an individual to the group where he lives. Labor markets only marginally affect crime, and the reasons are not entire clear yet. One environmental factor they do point to are durgs, specifically alcohol and heroin (the book came out before the crack epidemic broke in 1985, or surely crack would been included). These alter a persons time horizons and lead to impulsive behavior, as well as the need for money to support the habit. It is not clear how constitutional factors affect people in predisposing them to use drugs though. Perhaps they share some of the above constitutional traits.
After setting forth their model of criminal behavior as a choice that people make based on biological factors coupled with inadequate parenting, it seems only logical to expect policy suggestions on how to reduce crime. But they offer few. One reason is that since the book was both controversial and revolutionary, they were first interested in seeing their theory of criminal behavior become accepted. Since being written, it has indeed gained widespread acceptance, although it doesn't explain white-collar crime, and doesn't seem to explain organized crime either. The authors would counter that organized crime results from the same factors that they lay out in their general model. And it seems a valid point in explaining organized crime, who's members share many characteristics with petty criminals.
What is missing from the book is causation. After establishing an elegant an encompassing theory of crime which looks at both biological and environmental factors, the authors need to fill in the blanks. Most notably, why do mesomorphs show more criminal tendencies? And why do some men become criminals, while most don't? And how does one explain why women commit crimes? There is something notably missing here: How does one explain aggression, and the link between muscularity and aggressiveness?
Since 1985 researchers have closed in on the answer. It seems that the male hormone testoserone is responsible for aggression. Men with low testoserone claim to be tired, and unenergetic. After receiving the hormone, they say they feel better. No studies have been, however, to give men with high levels of testoserone more of the hormone for fear of uncontrolled behavior. Nonetheless, the correlation seems clear. It seems that mesomorphs, youths, and men all have higher testoserone than their counterparts. This explains their aggressive behavior. But even those three factors together cannot explain crime. Low intelligence, bad temperament, and poor parenting must also be factored in. A young man with high testoserone and a well adjusted personality will be highly successful. Indeed, society needs energetic young men to fight its wars, fight fires, and police the streets, among other jobs. It is only aggression in tandem with the other factors that is a problem.
Finally, we must address how to reduce crime, based on the model described here. One solution has been eugenics. The neo-Eugenics movement loved this book, using it to claim that crime is genetic, and to reduce crime all we have to do is sterilize criminals. While there is much in this book to support that claim, there will still be individuals born with these genetic traits. And most of all, society finds that solution abhorrent and unethical. I believe there are better ways to deal with criminals. If criminals are aggressive, impulsive, short-sighted young men, one way to deal with them is to slow them down. The tranquilizing effect of drug treatments would slow their impulses, and make them think before they act. No such drug has been introduced, but it seems like one could be not to far in the offing. Treatment programs like those offered by Stanton Samenow which help criminals by making them think about their every action, and what it will lead to in the future, could be done in tandem with drug treatment. By doing these things, along with strict policing, we can reduce crime greatly in our society.