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Spot the (alleged) criminal
Spot the (alleged) criminal
Politician
Estate agent
What are their alleged crimes?
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Musician
Today’s session
You are learning about...
You are learning to...
•
•
Critically evaluate
psychological theories
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Physiological theories of
criminal behaviour
Physiological theories
• Theories that link criminal behaviour to
biological form and function
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– Atavistic form (Lombroso)
– Somatotype (Sheldon)
– Extra Y syndrome
Atavistic form theory
• Lombroso (1876)
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– Criminality is inherited
– Genetic transmission of throwback/atavistic (i.e.
primitive) features
– Physical features indicate criminal tendencies
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Lombroso (1876)
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• Can you tell whether someone is a criminal
just by looking at them?
• How would you test this idea scientifically?
Lombroso (1876)
• A number of significant flaws:
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– Lack of a control group for comparison
– Sample included people with
psychological/physiological disorders
– ‘Crime’ is a social construction
– ‘Single defective gene’ theories - doubtful
Lombroso (1876)
• A number of significant contributions:
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– Later believed that most criminality was ‘acquired’
– environment, poverty, education
– Shifted study of crime to an empirical basis
– ‘The father of modern criminology’ (Shafer, 1976)
Somatotype theory
• Sheldon (1949)
– ‘Constitutional psychology’
– Criminality is linked to temperament
– Temperament is linked to bodily build
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• Ectomorph
• Endomorph
• Mesomorph
Relaxed and
hedonistic
Energetic
and
adventurous
Solitary and
restrained
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Source: www.pponline.co.uk
Sheldon (1949)
Sheldon (1949)
• The mesomorph’s personality makes him
more likely to engage in criminal activity
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– Thousands of photographs rated 1 – 7 for
mesomorphy
– College students & delinquents compared
– Delinquents had higher mesomorphy ratings (4.6
vs. 3.8)
Sheldon (1949)
– Influence of testosterone on body and behaviour?
– Effects of stereotyping and labelling?
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• Sheldon’s constitutional psychology is no
longer taken seriously
• But there is a small association between
bodily build and criminality. How could this
be explained?
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• Last year you looked at the effects of sex
chromosome abnormalities on development.
What did you learn?
Chromosomal abnormalities
XXY
XYY
Male with
feminine
characteristics
Male with
exaggerated male
characteristics
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XY
Chromosomal abnormalities
• ‘Extra Y’ syndrome was suggested to lead to:
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– High testosterone levels
– Powerful bodily build
– Heightened aggression
– Propensity for violent crime
Chromosomal abnormalities
– Normal testosterone levels
– Normal aggression levels
– Taller, but not necessarily more powerful
– Prone to developmental disorders and learning
difficulties
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• XYY males not actually as predicted (Graham
et al, 2007):
Chromosomal abnormalities
• XYY males are rare in the general population
and over-represented in the offender
population
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– However, their crimes are not violent ones
– So why are XYY men at a greater risk of offending?
• Single factor theories of criminality are always
likely to fail
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– ‘Crime’ is not a natural or homogenous category
of behaviour
– It is self-evidently the result of interaction
between a range of factors
– Different explanations for different types of crime