Forensics Module

Canter et al. (2004), using a technique called smallest space analysis, analysed data from 100 murders in the USA. The detaila of each case were examined with reference to 39 characteristics thought to be typical of organised and disorganised killers. Although the findings did indeed suggest evidence of a distinct organised type, this was not the case for disorganised which seems to undermien the classification system as a whole.

Nevertheless, the organised/disorganised distinction is still used as a model for professional profilers in the US and has widespread support. 

Canter's Circle theory (Canter and Larkin 1993) proposed two models of offender behaviour:

-The Marauder, who operates on close proximity to their home base.
-The commuter, who is liekly to have travelled a distance away from their ususal residence. 

Crucially, though, the pattern of offending is likely to form a cirlce around their usual residence, and this becomes more apparent the more offenders there are. Such spatial decision making can offer the investigative team important insight into the nature of the offence, i.e. whether it was planned or opportunistic, as well as revealing other important factors about the offender, such as their 'mental maps', mode of transport, employment status, approximate age, etc.

Canter and Hertiage (1990) conducted a content analysisof 66 sexual assault cases. The data was examined using the statistical technique smallest space analysis- a computer program that identifies correlations across patterns of beahviour. Several characteristics were indentified as common in most cases, such as the use of impersonal languageand lack od reaction to the victim. These charcteristics will occur in different patterns in different individuals. This can lead to an understanding of how an offender's behaviour may change over a series of offences, or in establishing whether two or more offences were committed by the same person. This supports the usefulness of investigative psychology becuase it shows how statistical techniques can be applied. 

In 1876, Lombroso, an Italian phsyician, wrote a book, called L'Huomo Delinquente within which he suggested that criminals were 'genetic throawbacks' - a primitive sub-species who were biologically different from non-criminals. By today's standards, Lombroso's theory of atavistic  form would be best as speculative and naive, though he is credited as moving criminology into a more rigorous and scientific realm, and his ideas may well have laid the foundation for the modern offender profiling techniques that were to follow. 

Offenders were seen by Lombroso as lacking evolutionary development, their savage and untamed nature meant that they wiyld find it impossible to adjust to the demands of civilised society and would inevitably turn to crime. As such, Lombroso saw criminal behaviour as a natural tendency, rooted in the genealogy of those who engage in it. 

Lombroso argued, the criminal sub-type could be identified as being in possession of particular physiological 'markers' that were linked to particular types of crimes. These are biologically determined 'atavistic' characteristics, mainly features of the face and head, that make criminals physically different from the rest of us.

In terms of cranial characterisitics, the atavistic form included a narrow, sloping brow, a strong prominent jaw, high cheekbones and facial asymmetry. Other physical markers included dark skin and the exsistence of extra toes, ******* or fingers.

Lombroso went on to categorise particular types of criminal in terms of their physical and facial characteristics. Murderers were described as having bloodshot eyes, curly hair and long ears; sexual deviants- glinting eyes, swollen, fleshy lips and projecting ears, whilst lips of fraudsters were thin and 'reedy'.

Besides physical traits, Lombroso suggested there were other aspects of the born criminal including insensitivity to pain, use of criminal slang, tattoos and unemployment.

Lombroso meticulously examined the facial and cranial features of hundreds of Italian convicts, both living and dead, and proposed that the atavisitic form was associated with a number of physical anomalies which were key indicators of criminality.

In all, Lombroso examined the skulls of 383 dead criminals and 3839 living ones, and concluded that 40% of criminals acts could be accounted for by atavistic characterisitics. 

Evidence suggests there may be neural differences in the brains of criminals and non-criminals. Much of the evidence in this area has investigated individuals diagnosed with antisocial personality disorder (formerly referred to as psychopathy). APD is associated with reduced emotional reponses, a lack of empathy for the feelings of others, and is a conditioned that characteristics many convicted criminals.

Prefontal cortex- Raine has conducted many studies of the APD brain, reporting that there are several dozen brain-imaging studies demonstrating that individuals with antisocial personalities have reduced activity in the prefrontal cortex, the part of the brain that regulates emotional behaviour. Alongside this, raine and his colleagues (2000) found an 11%  reduction in the volume of grey matter in the prefrontal cortex of people with APD comapred to controls.

Mirror neurons- Recent research suggests that criminals with APD can experience emapthy but they do more sporadically than the rest of us. Keysers et al (2011) found that only when criminals were asked to empahise (with a person shown in a film in pain) did their empathy reaction (controlled by mirror neurons in the brain) active. This suggests that APD individuals are totally without emapthy, but may have a neural 'switch' that can be turned on and off, unlike the 'normal' brain which has the empathy switch permanently on.

Proposed that behaviour could be represented along two dimensions: introversion/extraversion (E) and neuroticism/stability (N). The two dimensions combine to for a variety of personality characteristics or traits. Eysenck later a 3rd dimension- psychoticism (P).

Psychological explanations of offending shift the focus away from biological causes of crime towards social and psychological influences. These include the influence of dysfunctinoal learning environments and the influence of the family, cognitive factors and personality.

Eysenck's theory is something of a 'halfway house' in this respect. Even though his theory of the criminal personality would be classed as psychological- he does argue that all personality types have a biological basis.

There is often talk in the media about whether it is possible to delve into and better understand the criminal mind, which suggests that criminal activity might have a cognitive basis.

There are two main theories, one of these builds on the work of Kohlberg which claims that crimes may be committed by individuals who have a lower level of moral reasoning than non-criminals.

All psychodynamic explanations originate from the work of Freud. Although, Freud did not address the issue of criminal behaviour himself, other researchers have attempted to apply some of his key concepts to offending, such as the triartite structure of personality.

Bowlby's theory of maternal deprivation abide's by the Freudian principle that the roots of (criminal) behaviour is formed in childhood. This is supported by Bowlby's 44 thieves study.