Unit 2 - Criminological theories - 2.1 Describe biological theories of criminality Flashcards
Physiological theories - Lombrosso’s theory ‘born criminals’
According to Lombrosso, how do criminals differ from non-criminals?
Physically different
What research did Lombrosso carry out?
He spent years measuring and recording details of the heads and faces of thousands of prisoners
What did Lombrosso conclude from his research?
Criminals could be identified by their distinctive physical features such as large jaw, handle-shaped ears and high cheek bones
What is meant by ‘Atavism’?
Criminals are a throwback to an earlier primitive stage of evolution
Why were criminals like savages?
They were pre-social, unable to control their impulses and have a reduced sense of pain hence why they usually have tattoos
Explain why Lombrosso thought people were ‘born criminals’
He believed you could read their bodies for physical characteristics and that if they were born with specific physical characteristics you were destine to be criminal
What were two other types of criminals that Lombrosso identified?
‘Insane criminals’ and ‘epileptic criminals’
Sheldon’s somatotypes theory
How did Sheldon see criminals, similarly to Lombrosso?
Physically different from non-criminals and he believed certain body types are linked to criminality
Briefly describe the three somatotypes identified by Sheldon
Endomorph - rounded, tend to be fat, lacking muscle or tone with wide hips. sociable, relaxed, comfortable and outgoing
Ectomorph - thin and fragile, lacking both muscle and fat. They are flat chested with narrow hips and shoulders. Thin face and high forehead. Personality is self-concious, fragile, emotionally restrained and thoughtful
Mesomorph - muscular and hard bodied with little fat. Broad shoulders and thin waist. Personality is adventurous, assertive and sensation seeking
According to Sheldon who is the most likely to commit crime and why?
Mesomorphs - attracted to risk taking and their imposing physique can be an important asset in crimes like murder and rape
Genetic theories
What does the Cambridge study in Delinquent development show about crime in families?
Out of 397 families, half of all the convictions came in just 23 families
What did Osborne and West find out about crime in families?
Sons of criminal families were much more likely to have a criminal record too
Genetic studies - Twin studies
Describe how genetic theories explain why crime runs in families
Families who share blood share many of the same genes so therefore if a member has ‘criminal genes’ it is likely that their blood relatives will have them too, this is why criminals often have relatives who are criminals.
Why are twins used to test Genetic theories?
This is because Identical or Monozygotic twins share exactly the same genes so therefore if one twin is criminal the other twin is likely to be criminal too.
What evidence did Christiansens twin study in Denmark show?
He studied 3,586 pairs of twins. He found that their was a 52% concordance rate between identical twins where one twin has a conviction, there is a 52% chance the other will have a conviction. However, in non-identical twins there is only a 22% chance
What did the study of Ishikawan and Raine on twins show?
44% concordance rate for identical twins and only 21.6% for non-identical twins
Adoption studies
How do adoption studies test for genetic causes for crime?
Compares adopted children’s behaviour to their biological parents (genetic) and to their adopted parents (environment)
Explain how adoption studies could show a genetic link to crime
An adopted child shares the same environment as their adoptive parents, but the same genes as their biological parents. If we find that an adoptee’s behaviour in regard to criminality is more similar to their parents behaviour, this would support the genetic explanation
What does the evidence from Mednick’s Et Al study show about the genetic causes of crime?
He examined 14,000 adopted sons. They found that sons were 20% more likely to have a criminal record if a birth parent did and 14.7% if an adopted parent did.
Twin and adoption studies
Why are twin studies and adoption studies useful for researchers?
They help researchers to find out what we get from our genes and our environment
What are the Monozygotic and Dizygotic twins?
Monozygotic - twins that develop from the same egg so share 100% of genes
Dizygotic - twins that develop from separate fertilised eggs so share 50% of genes
What do Mono and Dizy twins both share?
Same environment like womb conditions
How are dizygotic twins different to regular twins?
Dizy twins share the exact same environment but regular siblings don’t eg parents are stricter with older child
What might doctors want to find out about Schizophrenia?
Whether it results from a genetic compound or effects from environments
How do twin studies allow scientists to isolate nature or nurture?
They can allow a constant environment but different genes
What problems are there with twin studies?
Mono twins might share more environmental similarities compared to dizygotic twins
How do adoption studies allow us to understand the difference between nature and nurture?
If a child is more similar to birth parents or adoptive parents
Why might adoptive studies not be ideal for understanding nature vs nurture?
There could be incomplete information about biological parents and adopted parents could be too similar to the biological parents
