IQ & Crime
Much research has
been conducted attempting to determine the link between IQ or intelligence
quotient and its possible link to crime rates among the general population. The
research question I found most interesting was, “What are the possible links
between IQ and Crime rates?” If IQ does in fact affect the crime rates, how
then do individuals (or parents, government leaders, teachers, etc.) go about
boosting the IQ rates of individuals in an attempt to help them resist crime?
Is IQ even alterable past the very early developmental stages in the fetus, or
is it merely chance; a mixture of genetic conditioning with random variability?
Attempting to determine the links between IQ and the correlations it may have
on crime statistics may be one way biologists can attempt to link with those in
the field of criminology in an attempt to find common ground.
What
studies have been done to show that IQ and crime may be linked?
- · A study done by Hirschi and Hindelang in 1977 conclude that IQ “was a powerful individual-level predictor of criminal behavior.”
- · A study in 1988 done by Kandel revealed that high-risk Danish males with high IQ were “protected” from criminal involvement.
- · Herrnstein and Murray in 1994 reported that white males in a correctional facility had an average IQ roughly 7 points lower than the population average.
- · McGloin and Pratt in 2003 found that individuals with lower IQ levels tended to have longer criminal careers, combined with a higher chance of beginning their deviance at a young age. (Researchers Piquero and White, also 2003, reported similar findings).
- · Beaver and Wright (2011) reported that county-level IQ was strongly correlated with county-level crime rates.
- · Criminal offenders score approximately 8 points lower, on average, on IQ tests when compared to the general population.
- · Nations with higher average IQs also exhibit lower rates of violent crime.
- · Inmates in another study received an average of 10 points below the national average, with a standard deviation of around 13 points compared to 15 for the general population, on an IQ test.
With
many different studies showing the strong correlation that exists between IQ
rates and crime rates at any level, what are things that may be done to
potentially raise the IQ of a child or adolescent?
- · Socioeconomic status, used to measure the quality of the environment in which children are born and raised, could be indicate of a nonlinear relationship between rearing environment and intelligence.
- · A healthy diet including fruit, vegetables, and fish was positively associated with IQ at 8 years of age. (Although the change in individual IQ scores was small, the effect on large populations of children could have greater significance).
- · It is possible that IQ is related to some variable that actually causes antisocial behavior.
- · Children whose mother’s IQ or quality of their home environment was low had poorer cognitive function when compared to those whose mother’s IQ or home environment quality was higher.
- · Studies show that the quality of the home environment has maximal impact in early childhood, while the mother’s IQ had maximal impact in later childhood.
- · A study done to show the effect of music lessons and IQ correlation among 6- to 11-year-olds showed positive correlation. These results indicate that formal exposure to music in childhood is associated positively with IQ and with academic performance and that such associations are small but general and long lasting.
- · A study in 1929 reported children ages 7-13 who had been breasted had better cognitive performance scores than children who had been artificially fed. It was also reported that at 7-8 years old, preterm infants of mothers who expressed breast milk for their infants had an average of 8.3 point IQ advantage over infants not provided breast milk.
- · An increase in the duration of breastfeeding was associated with increases in both verbal and performance IQ. Children who were breastfed for 8 months or longer had mean verbal IQ scores that were 10.2 points higher and performance scores that were 6.2 points higher, than the mean scores for children who did not receive breast milk. After control for confounding factors, there still remained a significant association between duration of receipt of breast milk and verbal IQ.
What
is it that may be the cause between lower IQ scores and higher crime rates?
- · Hare in 1984 reasoned that a delinquent life-style (i.e. drug abuse, violence, head injuries) results in lower intellectual functioning, although previous studies indicated that lower delinquent IQ scores were there well before the deviant acts were committed.
- · Another explanation in the same study suggests that delinquents score lower on IQ tests simply because they are not interested in doing well. This explanation assumes that delinquents are also personally oppositional or that test-taking is not of value to them.
- · Wilson and Herrnstein in 1985 found that at the individual level, there may be a distinction in IQ and the type of crime. Those offenders with lower IQs are more often violent offenders relative rather than those committing property offenses.
- · One of the more reliable theories is that IQ leads to delinquency through school failure (Hirschi, 1969). He reasoned that those boys who experience failure in school are more likely to become deviants than those who experience success in school.
- · Delinquents measured are approximately 8 IQ points lower than nondelinquents, on average.
- · A study done on arrests rates linking IQ, race, and socioeconomic status showed that lower verbal intelligence predicted a greater likelihood of arrest. Also as part of this study was numerous African countries, attempting to draw a link between IQ, race, socioeconomic status, and crime, and found that the crime/IQ relation held but the crime/skin color relation did not.
Correlations that
link crime and IQ seem to be present even when research is conducted at many
different levels. The problem with correlation crime and IQ may be that those
areas with high crime rates, such as the inner cities, may also be those where
the education tends to be the poorest. While there are definitely ways that the
IQ of children may be boosted, it is often up to the parent to do so, leading
to the issue of a lack of parents who may not be fully invested in their
children’s upbringing. Although most studies seem to show that most of the
intelligence and cognitive development seems to form in early childhood, there
may still be opportunities for schools to attempt to fight deviance through
education and cognitive reasoning. Through education, schools will not only
inform children properly of the effect that the decision to commit a crime may
have on their futures, but may also help with the reasoning that will allow
them to resist criminal situations later on in life.
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