criminology - biological theories

what was lombrosos theory (born criminals)

thought that facial features had a factor on if you were a criminal or not

what was lobrosos research

studied 4000 skulls of deceased criminals and said they werent as evolved as normal people

what was sheldons theory (somatotypes)

somatotyping - classifying people into body types

what was sheldons research

claimed that criminals who were prone to aggression were mesomorphs and the opposite was ectomorphs

what is meant by atavism

having primitive features - criminals are throwbacks to earlier and more primitive stages of evolution - unable to control impulses and had reduced sensitivity to pain

what are the physical features that demonstate criminality

- 40% had these

- big jaw, high cheek bones, handle shaped ears, prominent eyebrow arches, long arms, large eye sockets and acute eyesight

however, he didn't look at non-criminals so couldn't compare this

What were Sheldon's Somatotypes?

endomorphs, ectomorphs and mesomorphs

explain characteristics of endomorphs

- rounded and more soft, lacked muscle and had wider hips

-they were more sociable and relaxed

- fraud, money laundering, scams

explain characteristics of ectomorphs

- thin and fragile, lacking fat and muscle, flatter chests, narrower hips and thin faces

- more introverted and restrained

explain characteristics if mesomorphs

-muscular and hard bodied with little fat and strong limbs

- more aggressive, adventurous and sednsation seeking

- murder, shootings

what were the 3 strengths of Lombroso's theory

- was first person to study criminology scientifically using objective measures, before then was considered to be moral/religious problem

- challenged idea that criminals are evil or that they choose to be criminal

- took more holistic view - examining medical records and patterns of behaviour rather then individual criminal acts

what were the 2 weaknesses of Lombroso's theory

- research since has failed to show link between facial features and criminality

- not everyone with atavistic features is a criminal and not all criminals have them (deterministic)

what is the 1 strengths of Sheldon's theory

- most serious offenders in his sample has most extreme mesomorphic bodies

what are the 3 weaknesses of Sheldon's theory

- working class males more likely to commit crime and more likely to do manual physically demanding jobs which make them stronger - so criminality may be influenced by social class more than body type

- criminality may cause certain body types e.g. if someone wants to be feared they may change appearance to be more broad and muscular

- doesn't account for the endomorphs and ectomorphs who commit crime

what is the differance between monozygotic and dizygotic twins

monozygotic are identical twins that share 100% of heir DNA but dizygotic twins are fraternal twins and only share 50% of their DNA

what does concordance rate mean

the extent to which twins share the same characteristics

what did johannes lange (1929) find

that MZ twins had a higher concordance rate (10/13 sets) for criminal behaviour than DZ twins (2/17 sets) - suggests that when twins share 100% of DNA, they are most likely to both be criminals

what are the benefits of studying the behaviour of adopted children

can seperate genes and environment so they dont have biological parents to influence them without ethical issues

what was hutchings and mednicks (1977) aim method and results of their adoptive children experiment

aim - if theres a link between criminal convictions of adoptive children and their birth parents

method - studied 14,000 adopted children

result - a high proportion of boys with criminal convitions also had biologicsl parents with criminal behaviours

what are the qualities/characteristics of a super male/ xyy

behaviour problems - ADHD, autism. agressive, lack concentration, impulsive, have double testosterone

supporting reasearch for xyy chromosome causinf more crim

jacob (1965) said xyy chromosomes are overrepresented in prisons - 15/1000 in normal society = 1/1000

what are the 3 strengths of Jacobs XYY theory

- found a relationship between XYY syndrome and offenders imprisoned for violent behaviour

- XYY may be overrepresented in prison population due yo lower intelligence so more likely to get caught

- price and whatmore found links between the syndrome and property crime

what was the limitation of Jacobs XYY theory

- syndrome is very rare (1/1000 men) so cannot explain most crime

what are the 2 strengths of twin studies

- MZ twins are genetically identical so examining whether criminal behaviour is also identical is logical

- ishikiawa and raine found high concordance rate in MZ rather than DZ twins

what are the 3 weaknesses of twin studies

- if genes were only cause of criminality then MZ twins would have 100% concordance rates

- impossible to measure effect of genes separate from environment

- had a small sample size

what are 2 strengths of adoption studies

- overcome issue with twin studies - can separate influence of genes in the environment

- research found that adoptees were more likely to have criminal records if bio parents also had one

what are 2 weaknesses of adoption studies

- Gottfredson and Hirschi argue that adoption studies show that genes have little effect on criminality

- many children not adopted at birth so have grown up with bio family first - environment may influence criminality

what do brain injuries show

that there are some rare cases of brain injuries being identified as cause of criminality. some studies have shown that prisoners more likely than non prisoners to have suffered brain injuries. 64% of female offenders in drake hall have suffered a brain injury. schofeild in 2006 - 82% had a history of TBI + 65% lost consciousness

what do brain diseases show

some brain diseases have been linked with criminal/antisocial behaviour e.g. the 1920s epidemic of encephalitis lethargica among children was linked to destructiveness , impulsiveness, arson and abnormal sexual behaviour . other diseases like dementia, Huntington's disease and brain tumours have also been linked to deviant behaviour

what happened to Phineas gage and how did it affect his behaviour

was a railroad worker who survived a 3 foot 7 inch pole going through his left frontal lobe making it permanent damaged. he ended up have post traumatic personality change and became anti social, bad mannered and had band language (complete 360)

what do sex hormones in males show

the over/underproduction of certain hormones may lead to criminal behaviour e.g. testosterone has been linked to crimes such as murder and rape

what do sex hormones in females show

severe premenstrual tension, severe post natal depression and lactation have all been accepted as partial defenses for crime as it is claimed that hormones affect judgement, mood and self control e.g. a barmaid who had other convictions stabbed a barmaid 3 times in the heart got manslaughter due to PMS