Biological Theory: damage to prefrontal cortex
A biological theory of crime suggests that it is damage to the prefrontal cortex that disrupts peoples way of thinking. The prefrontal cortex centres on regulating concentration and peoples planning and organising behaviour.
Raine 1997 did a study that proved 41 murderers were found to have lower activity (less glucose metabolism) in their prefrontal cortex, and an imbalance was also found in the amygdale (emotion) and the thalamus (relay).
On the other hand, criminal behaviour cannot purely be the result of this brain defect as the brain is far too complex. It is most likely the result of many brain interactions and social predispositions.
Raine 1998 discovered that murderers that plan their crimes need their prefrontal cortex to be fully functional, however impulsive murderers do not. This suggests that some murderers are not responsible for the murders they have committed. A major limit to this theory is it can only be used to explain serious crimes – therefore it cannot be generalised to all crimes.
Biological Theory: Genetic
An alternate biological theory of crime is genetics. Family studies have shown that there was a 7% increase rate in criminal sons if their fathers had criminal records compared to sons with criminal records and non-criminal fathers; thus suggesting that we are influenced by our parents behaviour and social surroundings.
Adoption studies also have proved that genetics has an influence. Shown in a study: the amount people whose biological parents and adoptive parents had a criminal record was 24.5%, the highest figure in the study. If biological parents did have a criminal record but the adoptive parents didn’t, the figure was second highest at 20% of people.
To support this further, twin studies have shown a 44% concordance rate in monozygotic twins, as oppose to a 22% concordance rate in dygozygotic twins. However if crime was purely as a result of genetic the concordance rate in identical twins would be 100%.
The genetics theory does have many flaws; it would be morally wrong to discourage reproduction in people who have genes associated with criminal behaviour. As well as this informing people they carry genes associated with criminal behaviour would lead to labelling people and self-fulfilling prophecy.
The Social Theory: SLT
An alternate interpretation is social factors in explaining the reasons for crime. Biological theories are the explanation of more violent crimes – smaller crimes are more likely to be created by a social force (as they take planning).
Sunderland developed the Differential Association Theory which states that behaviour is learnt in particular social contexts: in which the petty crimes are not labelled as ‘abnormal behaviour’. Bandora’s study of aggression also supports this as it reinforces the theory that behaviour is copied, particularly in vicarious learning, where we copy behaviour depending on our observed reaction to someone else’s behaviour.
An alternative view to the influence of social factors is crime is a response to a situation that has been thought-out and planned: Rational Choice Theory (Cornish and Clarke). For example, a woman stealing to feed her family. Crime occurs at all levels in society, brain structure can be almost ruled out as people need a functional prefrontal cortex to carry out property crimes.
The Biopsychosocial Theory
The finally theory of crime is biopsychosocial, both factors have an influence on a variety of crimes.
Raine discovered a link between brain processors and deprivation in a childhood. A report stated that prisoners who had poor diets were more anti-social than prisoners who ate more vitamins and minerals; proving that biological and social factors have an influence.
To conclude, the evidence would suggest that the likelihood it is a mixture of nature and nurture theories that cause criminal behaviour seems the most likely, as to just assume one would leave out key factors that may be present.