Theories of CrimeBiology

Lombroso

•Lombroso in 1876 argued that the criminal is a separate species, a species that is between modern and primitive humans. He argued that the physical shape of the head and face determined the "born criminal".

Lombroso

                                                 

Can you notice anything about their features – anything in common?

William Sheldon

•Believed that people could be classified into three body shapes, which correspond with three different personality types.

Sheldon

Sheldon’s Body Types1.endomorphic (fat and soft) tend to be

sociable and relaxed. 2.ectomorphic (thin and fragile) are

introverted and restrained 3.mesomorphic (muscular and hard) tend

to be aggressive and adventurous.

•Sheldon, using a correlational study, found that many convicts were mesomorphic, and they were least likely to be ectomorphic (Sheldon et al 1949).

Could crime be genetic?

Normal Male

Spot the difference...?

• An extra Y chromosome – meaning some males can be described as XYY.

Genetic - XYY

XYY Male

Jacobs et al (1965) suggested that men with the XYY syndrome were more aggressive than normal 'XY' men. XYY men are over-represented in the prison population. There are 15 sufferers per 1,000 in prisons and 1 per 1000 in the general population.

For you to do....

•Collect a laptop and do some research on the XYY theory.

•Make sure you fully understand what is meant by XYY syndrome.

•Find out more details about the theory and try to find crime cases where this phenomenon has been involved.

•Read this - http://socialscience.stow.ac.uk/criminology/criminology_notes/genetics.htm

•Give the evidence to disprove XYY theory.

Neurophysiological

•Raine 1994 used PET scans to study the living brains of impulsive killers. Damage was found in the pre-frontal cortex, which controls impulsive behaviour. The task used involved sustained attention. It involved watching a screen for 32 minutes and responding every time an 0 appeared. Impulsive individuals also missed many of the 0s. Oddly enough, pre-frontal under arousal has also been found in politicians!

Neurochemical •The brain’s chemistry can be influenced by

diet, for example, food additives, pollution or hypoglycaemia (low blood sugar levels associated with forms of diabetes).

•Dawn Stanton attacked her husband with a knife when hypoglycaemic. But not all diabetics without insulin act criminally.

•More reading on this....http://webcache.googleusercontent.com/search?

q=cache:NVON5SIf1gIJ:jrscience.wcp.muohio.edu/Research/HNatureProposalsArticles/Final.TheInstinctofSurviv.html+dawn+stanton+diabetic&cd=10&hl=en&ct=clnk&gl=uk&source=www.google.co.uk

Neurochemical

•Individuals who take large amounts of steroids can become extremely violent (known as "roid rage").

•Steroids, usually taken to increase muscle growth, also increase testosterone levels.

•Horace Williams, a body builder, beat a man to death after taking two thousand times the recommended dosage of steroids.

Monozygotic twins

Twin studies •An 'MZ apart' study is when two

monozygotic children have been brought up apart. If both turn out to be criminals then this would be support for the genetic explanation. The degree of similarity between two twins is known as the concordance rate. This rate can then be compared with dizygotic twins who are brought up together ('DZ together').

•Looking at a number of studies the average concordance rate is 55% for MZ twins and 17% for DZ twins (Bartol, 1999).

adoption studies

Biological parents have criminal record

Adoptive parents have criminal record

% of sons with criminal record (Mednick 1987)

% of sons with criminal record (Bohman, 1995)

No No 13.53

Yes No 20.0 12

No Yes 14.7 7

Yes Yes 24.5 40

For you to....•Read the information on twin / adoption studies.•Write a couple of paragraphs that sum up the findings of

the two pieces of research done.•Go online and find evidence to either further support or

criticise the research. The following link will give you a good starting point;

http://law.jrank.org/pages/784/Crime-Causation-Biological-Theories-Genetic-epidemiological-studies.html