Since the beginning of time when crime emerged in society, many biological and psychological theories have come forth in attempting to dig up the root of criminal behaviour. Crime and criminal behaviour are issues that all societies face, and different approaches provide different outcomes and methods in how criminal behaviour can be prevented, treated, and assessed. Biological approaches have roots in controversial and flawed theories that have developed to sophisticated and logical studies and theories (Anderson, 2015, pp. 145-146). However, it is crucial to understand that a person’s biology and genetic makeup doesn’t directly cause criminality in a person, but instead can impact behaviours that can predispose someone to commit a criminal act. Rehabilitation are one of the solutions that come out of biological explanations of criminal behaviour; when the genetic root of the problem is discovered, it is very possible to alter one’s genetic future through lifestyle changes (Anderson, 2015, p. 146).
Psychological approaches offer another viewpoint to discover the root of criminal behaviour. There are several approaches in psychology that are relevant in explaining different components of criminal behaviour, such as psychoanalysis, behaviourism, social cognitivism, and developmental psychology (Heidt, 2015, p. 169). While both biological and psychological have influence on the criminal justice system, psychological theories have more impact in “areas of correctional treatment and risk assessment” (Heidt, 2015, p. 185). Several approaches are necessary to look at the true explanation of criminal behaviour as behaviour in general cannot be rooted to a single cause, but instead “a combination of many factors” (Anderson, 2015, p. 146), including biology and psychology (Cartwright, Heidt & Boyd, 2015, p. 119; Anderson, 2015, p. 146). Biological and psychological approaches work together to provide coherent explanations of criminal behaviour and biological predispositions and psychological personality and environmental factors need to be accounted for in order to provide the best insights into criminal behaviour.
Heritability, Adoption and Twin Studies
Criminal activity or behaviour cannot be linked to a single gene or characteristic, and when looking at inherited characteristics or genetics relating to criminal behaviour, there are environmental and other psychological factors that plays into whether an individual will show criminal behaviour or commit a crime (Anderson, 2015, p. 146). In twin and adoption studies, biological approaches are mainly focused in using concordance rates to compare the traits of monozygotic (MZ) and dizygotic (DZ) twins. MZ twins, also known as ‘identical twins’, are the result of a single sperm fertilizing a single egg and share 100 percent of the 1 percent of DNA that determines difference in characteristics (Anderson, 2015, p. 147). DZ twins, on the other hand, are no different from regular siblings, and are the result of two sperm fertilizing two eggs. DZ twins only share 50 percent of their DNA (Anderson, 2015, p. 147). Concordance rates, the proportion of pairs that share a certain characteristic, are often used in studies involving twins.
In Adrian Raine’s 1993 meta-analysis of 13 twin studies, the concordance rates for crime in MZ twins was found to be higher than concordance rates for crime in DZ twins (cited in Anderson, 2015, p. 148). Though results from biological twin studies may suggest that a particular trait or disorder has a genetic component, it does not provide information about the location of the gene or genes. However, a biological approach in twin studies is still extremely useful in understanding which traits, behaviours or disorders are environmentally affected, and which are inherited components.
Examining environment along with heritability of characteristics is important grasping to which extent the behaviour is influenced by genetic factors. Through adoption studies, genetic and environmental influences can be separated to compare criminal behaviour of people, even twins, who were adopted by non-family members with that of their adoptive and biological parents (Anderson, 2015, p. 149). Most adoption studies present a higher level of criminal behaviour in adoptees with criminal biological parents for non-violent crimes, and this is reflected in a Danish adoption study, where there was a clear indication of increased concordance rates for property crime criminal records with genetic relationship (Mednick, Gabrielli & Hutchings, 1987, as cited in Anderson, 2015, pp. 149-150).
In regard to concordance rates of juvenile and adult crimes, reanalysis of twin studies of a self-reported study in the US showed a greater concordance rate of influence on genetics in adult crime and a greater concordance rate of environmental factors in juvenile crime (Lyons, 1996, as cited in Anderson, 2015, p. 148). Reanalysis of twin studies all over the world have shown that the etiology of juvenile and adult criminal behaviour are not the same and rooted in very different factors. Twin studies in this regard have been very valuable in showing that biological and psychological (environmental) factors cannot be studied without one another (Anderson, 2015, p. 148).
Sigmund Freud’s Psychoanalysis
Sigmund Freud’s psychoanalysis approach claims that there are three parts to the personality: the id, superego, and ego (Heidt, 2015, p. 172). The id is instinctive component of personality and stems from biological and inherited parts of personality, including urges for aggression and sex (Redl & Toch, 1979; Andrews & Bonta, 2010, as cited in Heidt, 2015, p. 172). Neurotransmitters, including dopamine, serotonin, norephedrine, have influence on the personality. Dopamine and norephedrine can have unfavourable effects on personality when they are at levels above the normal, which may cause increased aggression (Coccaro & Kavoussi, 1996; Young et al. 2002, as cited in Anderson, 2015, p. 154). Impulsive-aggressive behaviour and inability to cope with stress is linked to low levels of serotonin, however, biological predispositions, including the impact of dopamine, serotonin and norephedrine, may only influence behaviour under certain environmental conditions (Heidt, 2015, p. 172). For example, as Freudian criminologists linked criminality to “problems in childhood resulting from poor parenting practices”, placing emphasis on the importance of family and early childhood development (Heidt, 2015, p. 172).
The superego, another component of the personality according to psychoanalysis, is essentially the conscience, moral compass of an individual and develops through maturity (Heidt, 2015, p. 172). An overactive superego can result to increased feelings of guilt, leading to neurotic offenders that commit crimes with the intent to be punished to lessen the feeling of guilt (Freud, 1920, 1923, as cited in Heidt, 2015, p.172; Heidt, 2015, p. 172). In another case, when the superego fails to develop properly, psychopathic personality including failure to be remorseful and lacking a conscience (Andrews & Bonta, 2010, as cited in Heidt, 2015, p. 173). It is important to note that psychopathy is a personality disorder, and not to be used interchangeably with sociopathy which is now used to refer to those with anti-social personality disorder (Heidt, 2015, p. 174). As well, not all criminals are psychopaths, in fact most psychopaths never have to encounter the criminal justice system, therefore, psychopathy isn’t reasonable to assume that all psychopaths are more violent and aggressive that others (Heidt, 2015, pp. 174-175).
Lastly, the ego, mediator of the superego and id, is the aspect of personality that functions by assessing the demands of the real world to act accordingly. A weak ego often also involves an unregulated id, and therefore, a weak ego can lead to failure to control one’s behaviour, impulsiveness, and even distorted perceptions of reality and self. Through assessing Freud’s psychoanalysis theory, it is apparent that both psychological and biological approaches are necessary in explaining the way components of the personality can influence behaviour.
Intelligence and Crime
In Henry Goddard’s study of the Kallikaks, Mr. Kallikak fathered one family with a reportedly ‘feeble-minded’ barmaid and another family with a Quaker woman and found that the family with the Quaker woman exhibited little criminal behaviour while the other side exhibited a “great deal of criminality” (Heidt, 2015, p. 170). Instead of suggesting heredity of criminality, Goddard came to the conclusion that feeble-mindedness was an inherited trait and that “less intelligent people were at greater risk for criminality” (1913, as cited in Heidt, 2015, p. 170). In support to Goddard’s conclusions, Fishbeing noted that “intellectual deficits, which are closely tied to delinquent and criminal lifestyles … are understood to be largely heritable” (1990, as cited in Cartwright, 2018), however, it is crucial to note that IQ or intelligence on its own is not proven to be a predictable element of criminal behaviour (Cartwright, 2018).
Feeblemindedness or low IQ has shown to contribute to criminality but does not cause criminality on its own. Hirschi and Hindelang’s 1997 article on intelligence and delinquency argued that intelligence does not have direct impact on criminal behaviour, however does affect criminality indirectly through poor school performance, leading to other problems such as negative labelling or problems with authority figures like teachers or principals, which may result in reduced employed opportunities, which all increase the likelihood of criminal behaviour (as cited in Heidt, 2015, pp. 170-171). Studies on the link between intelligence and criminal behaviour may suggest that intelligence or ‘feeble-mindedness’ are inherited, but the predisposition still relies on environmental factors to relate it to criminality.
Conclusion
Through discussing several theories and studies, it is evident that both biological and psychological approaches are not as different as they may appear to be and in fact work together to produce well-rounded, scientific approaches to explaining criminal behaviour. Biological predisposition to crime because of genetics or inherited characteristics and psychological factors such as intelligence and environmental factors alone does not directly influence whether an individual will commit a crime or show criminal behaviour. Rather, it can be seen as complementary viewpoints, as those factors working together may lead to negative outcomes that can increase the likelihood of an individual committing a criminal act.