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Spot the (alleged) criminal

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Spot the (alleged) criminal

Musician

Politician Estate agent

What are their alleged crimes?

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Today’s session

You are learning about... You are learning to...• Physiological theories of

criminal behaviour• Critically evaluate

psychological theories

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Physiological theories

• Theories that link criminal behaviour to biological form and function– Atavistic form (Lombroso)– Somatotype (Sheldon)– Extra Y syndrome

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Atavistic form theory

• Lombroso (1876)– 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?

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Lombroso (1876)

• A number of significant flaws:– Lack of a control group for comparison– Sample included people with

psychological/physiological disorders– ‘Crime’ is a social construction– ‘Single defective gene’ theories - doubtful

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Lombroso (1876)

• A number of significant contributions:– 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)

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Somatotype theory

• Sheldon (1949)– ‘Constitutional psychology’– Criminality is linked to temperament– Temperament is linked to bodily build• Ectomorph• Endomorph• Mesomorph

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Sheldon (1949)

Relaxed and hedonistic

Energetic and

adventurous

Solitary and restrained

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Sheldon (1949)

• The mesomorph’s personality makes him more likely to engage in criminal activity– Thousands of photographs rated 1 – 7 for

mesomorphy– College students & delinquents compared– Delinquents had higher mesomorphy ratings (4.6

vs. 3.8)

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Sheldon (1949)

• 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?– Influence of testosterone on body and behaviour?– Effects of stereotyping and labelling?

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• Last year you looked at the effects of sex chromosome abnormalities on development. What did you learn?

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Chromosomal abnormalities

XYXXY

Male with feminine

characteristics

Male with exaggerated male

characteristics

XYY

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Chromosomal abnormalities

• ‘Extra Y’ syndrome was suggested to lead to:– High testosterone levels– Powerful bodily build– Heightened aggression– Propensity for violent crime

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Chromosomal abnormalities

• XYY males not actually as predicted (Graham et al, 2007):– Normal testosterone levels– Normal aggression levels– Taller, but not necessarily more powerful– Prone to developmental disorders and learning

difficulties

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Chromosomal abnormalities

• XYY males are rare in the general population and over-represented in the offender population– However, their crimes are not violent ones– So why are XYY men at a greater risk of offending?

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• Single factor theories of criminality are always likely to fail– ‘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