Small though: what are the consequences of regarding crime as a disease?


  • Criminals are labelled, making it easier for treatment to be given
  • It provides criminals with an explanation for their behaviour
  • This may promote more funding to be directed towards treatments for offenders which, with success, could lead to lower offending rates in the long term
  • Self-fulfilling prophecy: false beliefs are put into the minds of the criminals, leading to psychological distress and a rise in criminal activity
  • It implies determinism but the criminal justice system is based on the idea of free will: a losing situation

Early biological explanations for offending: ‘criminals are born, not made’


  • Lombroso (1876) believed that ‘throwback’ characteristics, coded for by a single defective gene, contribute to the atavistic (primitive) form: a different species of distinct physical characteristics such as thicker eyebrows and higher cheekbones. As well as different physical features, these people had criminal behaviour.

No single gene has been found to cause criminal behaviour or to contribute to common criminal characteristics. Though Lombroso’s work lacked control groups and included people with psychological and physical disorders, he shifted the study of crime to a more empirical basis. He later believed, after proposing the atavistic form, that crime actually occurred due to environmental factors. This gave rise to the line of though that biological and environmental factors together result in criminal behaviours.

  • Sheldon‘s somatotype theory (1949) states that criminality is linked to temperament, which is a result of their constitution. Ectomorphs, tall and skinny, are solitary and restrained. Endomorphs, short and round, are relaxed and hedonistic. And mesomorphs, those believed to possess the ‘criminal build’, are hard and muscular, energetic and adventurous.

Sheldon rated thousands of photographs of college students and delinquents, and found that delinquents had a higher mesomorph rating. Though a large data set was used, the subjective scale and large experimenter bias concludes this study as invalid. Sheldon also did not use legal criteria, but when it was used, it was found that an association between criminal activity and constitution was not present (Sutherland 1951). Similarly, Putwain and Sammons (2002) criticised the approach as it rests on the stereotyping and labelling of mesomorphs, instead leading to their criminality rather than the body type directly.

  • Chromosomal abnormalities – The ‘extra Y syndrome’, which gives males another Y chromosome at prenatally, contributes to increased dominantly masculine traits, including aggression as these individuals possess more testosterone.

Though this is a logical theory, many studies are inconsistent with it. it has been found that XXY males are not actually as predicted (Graham et al 2007). These individuals have normal testosterone and aggression levels; they are taller but not necessarily more powerful. They are prone to developmental disorders and learning difficulties, which may perhaps make them more prone to criminal activity. Witkin et al (1976) found that 12/4500 men had the extras y syndrome but none of these 12 were offenders. Though XXY is rare in the normal population but over represented in the criminal population (Epps 1995), there is self evidently a range of environmental factors which also affect the likelihood of offending.

Perhaps then, as both nature and nurture are seen to affect the likelihood of offending, the diathesis stress models should be adopted. Factors considered in modern biological theories, such as Taumatic Bain Injury (TBI) do just this.

Should brain scans be used in the courtroom?


Roughly 5% of murder trials in the USA now involve some aspect of neuroscience in the process of coming to an overall verdict. As technology advances, we are increasingly able to provide and incorporate it into the process of meaningful societal decisions. But should brain scans be used in the courtroom?


  • The authors of the Royal Society panel, including Nicholas Mackintosh of the University of Cambridge, flag up research suggesting that the brains of psychopaths are fundamentally different to the brains of non-psychopaths. Therefore, brain scans would be crucial to determining whether or not a suspect is guilty of committing crime due to free will, as a psychopath’s disorder and subsequent altered brain structure would account for their lack of control in committing the crime. 
  • Similarly, recent research into brain development suggests that crucial brain regions such as the prefrontal cortex, which is important in decision making and impulse control, don’t actually finish maturing until the age of around 20.  
  • Brain scans provide sound methodology due to their empirical nature and objective rigour. This is seen as a desirable step forward in the courtroom as it improves accuracy of convictions by the implementation of science. The gradual removal of dependence upon subjective decisions, which are left open to the possibility of biased interpretation and subsequent inaccurate conviction, are thus seen as a good thing.


  • Lie detection research is often based on students telling lies that are unlikely to have any impact on their lives. This provides a situation that’s difficult to compare to a criminal who might be lying for his life, not to mention that of a cunningly deceptive psychopath. The lack of generalisability is arguably too great an issue to risk in serious decisions such as murder trials. Additionally, most fMRI studies are small, unreplicated and compare differences in the average brain activity of groups, rather than individuals, making it difficult to interpret for single cases. It is rarely used in diagnosis. Moreover, a recent scan, say some critics, wouldn’t necessarily indicate a criminal’s mental state when he committed his crimes, weeks, months or ever years before the scan is taken.
  • Criminals may simply learn how to trick the system. The scientific brain scans rely on physiology to generate decisions but criminals may possess biofeedback control, allowing them to manipulate their physiology. The evidence calls them innocent but they’re just playing science.
  • The easy manipulation of brain scans is confirmed by the results of one experiment, in which the success rate for distinguishing truth from lies dropped from 100% to a third when participants used countermeasures. The researchers of this study concluded that, “for the foreseeable future reliable fMRI lie detection is not a realistic prospect.”

Conclusion?:There is no harm in slowly bringing more brain scan use into the courtroom, as long as their scientific label does not cause them to be mistaken for a perfect machine of criminal judgement. They should be used with caution and not overly relied on, as a useful tool and step towards more accurate verdicts of cases involving brain injury litigation or questions of impaired ability. Their use will be a win for those who believe in biological determinism, which may fire up the old nature-nurture debate once more.