Development of Criminal Mind: Nature Vs. Nurture

A number of studies conducted in many countries over the years have come to similar broad conclusion which clearly indicates that genes play a significant role in determining criminal behavior. There are of course no specific genes associated with criminal tendencies nor any specific set of genes that can directly code for criminal behavior is assumed to exist. Rather, a wide variety of genes acting in a deadly concert bring about various degrees and types of genetic predisposition to criminal behavior.
The term predispostion indicates a potential tendency that needs suitable environmental factors to trigger it. Criminal behavior is caused both by environmental and genetic influences, and most often it happens through a complex interaction between them. Crime is neither genetically nor environmentally determined, but there are often strong heritable influences in criminal behavior as well as noticeable environmental causes. For example, adoption studies investigating the nature vs. nurture issue in criminal behavior have found a surprising degree of genetic influences in criminal behavior.
Less surprisingly, but as certainly, they have been able to identify the role of numerous adverse psychological and social factors in actualizing criminal behavior. The relative importance of heredity and environment in determining human behavior has long been a seriously debated issue. In the early decades of the twentieth century, for example, William James believed that our behavior is largely shaped by the power of instincts and inherited tendencies present at birth.

Quite in contrast to James, John Watson, the founder of Behaviorism, believed in the power of conditioning, and the infinitely plastic human capacity to be molded by the forces of environment (Butterfield 2004). Although animal behavior can be easily conditioned too, it is heavily determined by the animal’s genetic programming. In the case of humans, the situation becomes complicated because of the presence of a superior intelligence. Humans are enormously impressed and influenced by their environment.
They also can readily learn from their environment and adapt their behavior accordingly. Yet by no means can the hereditary factors be easily dismissed. It can be easily observed in day to day life that children with different genotypes react differently to the same environments and seek out different experiences. A child who is active and aggressive by innate temperament would obviously react in a different way, for example, to the parental commands such as “Do this” and “Stop doing that” than his sibling who may be more passive or docile.
All of us have a general notion of right and wrong. But the criminal orientation of mind which tends to flout many of these accepted notions of right and wrong usually begins to form at a very early age in life. Heritability is an important determinant in a wide variety of personality factors. Criminality, along with a wide variety of specific characteristic traits associated with it such as aggressiveness, impulsivity or novelty-seeking, is no exception (Ebstein & Belmaker 2002).
A few decades ago it was believed that that genetics played no part in formation of antisocial and criminal behavior. However, a great deal of research work since then attesting to the fact that genetic factors are as important to the development of at least some forms of criminal activity as are environmental factors (Ishikawa & Raine 2002). Behavior-genetic research in the recent decades has attributed 25% to 75% of variances in many reliably measurable psychological traits to genetic differences (Lykken 1998).
The notion of inherent badness or “the bad seed,” which apparently goes against many deeply held democratic notions in our society such as the principle of “All men are born equal,” would seem to be very difficult to swallow for the more liberal minded among us. Many of us generally tend to place the blame on poverty, parental abuse, poor child-rearing, or some childhood trauma etc, or at least used to do so before the current fad of placing everything on genes developed.
The truth, however, is that although “the bad seed” is a very real factor to reckon with, it can usually grow only in a bad soil, perhaps additionally requiring deprivation of sunshine and rain (Zuckerman 2002). To date, there is already considerable evidence from twin and adoption studies of a moderate effect of genetics in chronic criminality. Two reviews have surveyed the available literature and found that with one exception all the 15 major studies indicate evidence for a significant element of genetic predisposition.
It is remarkable that researchers in different countries and cultures have discovered compatible evidence (Eysenck 1998). Twin studies of juvenile delinquents show no significant disparity between identical and fraternal twins, thereby indicating a greater impact of environment over and above the effects of genetics. However studies in adult criminality show concordances for fraternals and identicals in the ratio of 1 is to 2, indicating a significant genetic predisposition.
In adoption studies, evidence from one particular large study of criminal behavior in adopted children in Denmark has shown that there is a noticeable tendency for these children to pursue a path of antisocial behavior, unconsciously following the path of their biological parents (Steen 1996). A study examined the conviction record of over 14,000 adopted sons to that of their biological and adoptive parents. The results of this study demonstrated that the criminal record of adopted parents (environmental factors) has a minimal effect on adopted children.
In sharp contrast to this, if biological parents were convicted and not the adoptive parents, 20% of the adopted sons were also convicted. Such studies clearly show that the influence of absent genetic parents is significantly higher than the influence of environmental parents who may be very much present. Interestingly though, the inherited tendencies have been seen to come into play in this study only in regard to property crime and not in violent crime.
It has also been noticed that the adoptee was more likely to commit a crime if the biological mother had a criminal record. Here the theory is that since women are less prone to crime than men, if a woman has committed a crime she must have had a stronger genetic compulsion to do so, which her biological son was more likely to inherit despite him being brought up far away from her. In another study of similar nature, psychologists studied the records of 862 adopted men who were born out of wedlock in Stockholm between 1930 and 1949.
After extensive, meticulous and painstaking investigations into a slew of wide variety of records and data sources, information was compiled on the patterns of criminality, alcohol abuse, and medical problems, among other things, in the individuals as well as both in their biological and adoptive parents. The majority of the adoptees came from a genetic background that did not involve crime, were adopted into families with no taint of crime, and expectedly themselves displayed no criminal tendencies.
But various comparisons and analyses associated with the remaining data has shown that both genes and the environment had an effect in determining criminal behavior of the adoptees. However, on the whole, genes seemed to play a far more powerful role than environmental factors. Considering those children that were placed in regular non-criminal homes, a child from a genetically criminal background was four times more likely than a child from normal background to turn out as a criminal.
Nonetheless, it must be noted here that criminal behavior of the adoptees could rarely be directly associated with the supposed criminal genes, and most often there was a crucial interaction between genes and environmental factors, which seems to be very much necessary in instigating criminal behavior. Therefore while crime is a sociological concept and a number of determinants of criminal behavior are socioeconomic factors, there is a clear genetic component to crime which manifests in such personality traits as cognitive skills, impulsivity, sensation seeking, aggressivenss and hyperactivity (Millon, Simonsen, & Birket-Smith 1998).
Conclusion Today, it is generally believed that forces of both heredity and environment have a huge role to play in shaping up the character and psychological profile of any individual, though it cannot be easily ascertained to which degree one can override the other when both of them are in some kind of conflict. Adding to this complexity is the concept of free will in man.
True human dignity can arise if only there is free will, which can allow us to intelligently choose the best from both our heredity and environment, and voluntarily reject, or at least try to reject, those aspects which may not be conducive to the optimal expression of our potential. However, since the levels of intelligence are variable in humans, there may be no simply universal answer which can enlighten us on the general motive forces behind human behavior.
Free will, nature and nurture may all be playing out in different ways in different individuals, depending on the caliber of their individual intelligence, and the force of their unique circumstances and hereditary influences. Even in case of criminals, there may be no valid sweeping generalities, in terms of free will, nature or nurture. Yet, in as much as we need to clearly pin down the responsibility of each criminal act, the role of nature and nurture in determining the criminal behavior has to be investigated at more depth and on a more urgent basis, than in the case of general human behavior.
References:
Butterfield, R. (2004). A Psychological Profile Into The Criminal Mind. Philadelphia. PA : Xlibris Corporation
Ebstein R. & Belmaker R.H. (2002). Genetics of Sensation or Novelty Seeking and Criminal Behavior. In, The Neurobiology of Criminal Behavior, ed. J. Glicksohn. pp.  51-80.
Norwell, MA : Kluwer Academic Publishers
Eysenck H.J. Personality and Crime. (1998). The Case for Parental Licensure. In,  Psychopathy: Antisocial, Criminal, and Violent Behavior, ed. T. Millon et al. pp. 40-49. New York : The Guilford Press
Ishikawa, S.S. & Raine A. (2002). Behavioral Genetics and Crime. In,
The Neurobiology of Criminal Behavior, ed. J. Glicksohn. pp.  27-50.
Norwell, MA : Kluwer Academic Publishers
Lykken D.T. (1998). The Case for Parental Licensure. In,  Psychopathy: Antisocial, Criminal, and Violent Behavior, ed. T. Millon et al. pp. 122-144. New York : The Guilford Press
Millon T, Simonsen, E. & Birket-Smith, M. (1998). Historical Conceptions of Psychopathy in the United States and Europe. In,  Psychopathy: Antisocial, Criminal, and Violent Behavior, ed. T. Millon et al. pp. 3-31. New York : The Guilford Press
Steen R. G. (1996). DNA & Destiny: Nature & Nurture in Human Behavior. Cambridge, MA : Perseus Publishing
Zuckerman M. (2002). Personality and Psychopathy: Shared Behavioral and Biological Traits. In, The Neurobiology of Criminal Behavior, ed. J. Glicksohn. pp. 81-110.
Norwell, MA : Kluwer Academic Publishers