Biological theories of criminality

Question 1

Jacob’s XYY theory

Answer 1

A chromosomal abnormality wherea male has an extra Y chromosome, these men are referred to as ‘super males’. Jacobs suggests that the extra chromosome leads to increases testosterone so they are more violent and agressive, they are also more likely to have lower IQs

Question 2

Advantage of Jacobs XYY theory

Answer 2

*males with XYY are over represented in prisons 1.5% compared to 0,1% in the wider population
*Price and Whatmore found XYY males to be immature, unstable and have poor impulse control
*Adler et al indicated that it is possible that agressive and violent behaviour is at least partailly detemined by genetic factors

Question 3

Disadvatnage of Jacobs XYY

Answer 3

*Ignores the behaviourist approach and states that all behaviour is due to genetics and biological make up
*Studies caried out in prisons and mental health institutes which support the theory are unrepresenative
*many men with XYY will never commit or never committed a crime
*doesnt explain why women commit crime

Question 4

Twin studies

Answer 4

allow criminologists to compare those with identical DNA to those without which helps to remove some shared enviromental factors

Question 5

what are monozygotic twins and dizygotic twins

Answer 5

Monozygotic twins - identical twins, share 100% of their DNA
Dizygotic twins - non-identical twins, share 50% of DNA

Question 6

what is concordance rate

Answer 6

like likehood that is one twin has a certain traid, the other will also have the same traid

Question 7

Langes twin study

Answer 7

he found 77% concordnace between 13 MZ twins and 12% concordnace rate between 17 DZ twins

Question 8

Christiansen twin study

Answer 8

he studied over 3000 twins in Denmark and found that the concordance rate for MZ twins is 52% and 22% for DZ twins

Question 9

Advatnage of Twin studies

Answer 9

*they’re natural experimets, the biological relationship between twins is naturally occuring so the studies are ethical
*twins studies have helped the prevention of other disorders

Question 10

Disadvantages of twin studies

Answer 10

*Langes study has methological issues and he only assumed whether the twins were DZ or MZ based on their looks, he also had a sample
*Nurture could also be a factor since twins tend to live in the same enviroment and are socialised in the same way

Question 11

Adoption studies

Answer 11

Studying the effects of genetics on criminality whilst taking the enviromental factors out the equation

Question 12

Mednick adoption study

Answer 12

he studied 14,000 adopted sons in denmark and found that a high proportion of boys with a criminal conviction had biological parents with criminal convictions too
- in 20% of cases if birth parent had a criminal conviction so did the biological son
- only in 14% of cases if adoptive parent had a criminal conviction so did the adoptee

Question 13

Advantage of twin studies

Answer 13

*they have showed that there is a strong genetic influance to criminality
*they allow for the seperation of genetic and enviromental factors

Question 14

Disadvantage of adoption studies

Answer 14

*children who are adopted are placed into similar enviromnets to their bio parents so there still might be some enviromental factors
*some children are adopted at later age so early life experinces may cuase criminal behaviour

Question 15

Lombrosos theories

Answer 15

*he felt that criminals were a seperate species and evolutionary throwbacks
*whether someone is a criminal or not is determined by the physical shape of the head and the face.
*criminals has atavistic features

Question 16

Who did Lombroso use in his studies

Answer 16

383 dead crimianals and over 3,800 living prisoners and concluded that 40% had atavistic features

Question 17

Study from china (2012) to support lombrosos theory

Answer 17

a university used 1,800 ID photos of chinese man and entered them into an AI programme that aimed to identify criminals based on their physical features. The programme correctly identified 83% of the criminals

Question 18

Strenghts of Lombroso’s theories

Answer 18

*lombroso was the first person to give criminology scientific credibility
*his work was the basis for criminal offending
*challenages the idea that crimianls are evil/chose to be criminal

Question 19

Weaknesses of Lombroso’s theories

Answer 19

*not everyone with atavistic features is a criminal and not every criminal has them
*could be be accussed of scientific racism as many of the atavistic features he describes are specific to people of African descent
*the theory is deterministic and assumes that we cant’t change or escape destiny and that we have no free will

Question 20

What is Sheldon’s theory of criminality

Answer 20

he said that criminals are physically different from others and that there are 3 distinctive somatotypes (body types) each linked to personalities

Question 21

What is the endomorphic body type

Answer 21

fat and soft, they tend to be more sociable to relaxed

Question 22

What is the Ectomorphic body type

Answer 22

thin and fragile, they tend to be more introverted and restrained

Question 23

What is the mesomorphic body type

Answer 23

muscular and hard, they tend to be more aggressive and adventurous

Question 24

How did Sheldon study his theories

Answer 24

he used a correlation study of 4,000 men where he used pictues of college students and delinquents and he rated their resemblance to the mesomorph body type on a scale from 1 to 7. His results showed that delinquents had an average rating of 4.6 compared to 3.8 of college students.

Question 25

what is research to support Sheldon’s theory

Answer 25

Glueck and Glueck who found 60% of mesomorphs in a crim population and 31% in a non-crim population

Question 26

Strengths of Sheldons theory

Answer 26

*number of studies have confirmed that there is a small association between bodily build and criminality –> putwain & sammoson 2002
*sheldons studies had a substantial sample and a control group of non-offenders

Question 27

Limitations of Sheldons theory

Answer 27

*it doesn’t explain how other body types can be criminal
*it doesnt account for people’s somatotypes changing over their life
*labelling criminiality by body types may lead to that body type being treated more harshly and getting convicted more often

Question 28

How are brain injuries linked to criminality

Answer 28

studies shave suggested that damage to the pre-frontal cortex of the brain may cause a person to have an altered behaviour pattern ; becoming more immature, loss of self control, loss of emotional regulation

Question 29

Brain abnormalities Raine et Al (1994)

Answer 29

used PET scans to study the brains of living impulsive killers and found damage in the pre-frontal cortex

Question 30

Brain abnormalities Mclsaac et al (2016)

Answer 30

carried out a study in Canada which found those who has experienced serious head injuries were twice as likely to end up in prison.