AC2.1-Describe biological theories of criminality

Question 1

What are the 2 physiological theories?

Answer 1

Lombroso’s theory and Sheldon’s theory.

Question 2

What was Lombroso’s overall idea?

Answer 2

That there are distinguishing physical features of criminals, setting them apart as offenders.

He believed that criminals still possessed features of the neanderthal and proposed the ‘L’uomo delinquent’- the criminal man.

Question 3

How did Lombroso conduct his research?

Answer 3

He examined the features and measurements of 3839 criminals and the skulls of 383 dead criminals. He measured aspects like: people’s height, weight, span of arms, hand size.

40% of criminal acts were accounted for by people with atavistic characteristics such as: low sloping foreheads, long arms compared to legs, high cheekbones, large ears.

Question 4

What features did Lombroso link to theives?

Answer 4

expressive face, small wandering eyes.

Question 5

What features did Lombroso link to murderers?

Answer 5

bloodshot eyes, big hawk-like nose

Question 6

What features did Lombroso link to sex offenders?

Answer 6

thick lips, protruding ears

Question 7

What features did Lombroso link to women offenders?

Answer 7

shorter and more wrinkled, smaller skulls than ‘normal’ women.

Question 8

What general (NOT PHYSICAL) atavistic characteristics did Lombroso discover?

Answer 8

‘Pre-social’, did not get on well with others, unable to control impulses, reduced ability to feel pain: multiple tattooes.

Question 9

What were the strengths of Lombroso’s theory?

Answer 9

Lombroso challenged the idea that criminals are evil or that they chose to be criminal, he suggested that criminality was innate and criminals were not exercising free will when committing crime.
Allowed people to move away from the idea that all criminals were evil and to study alternative reasons as to why people commit crime.

He lent scientific credibility to the role of biology in criminology, when criminology used to be studied from a religious and moral ground. This allowed the study of criminology to gain scientific credibility.

Lombroso’s work has been used in development of offender profiling due to the physical traits he put forward such as high cheekbones. His work has had practical applications in attempting to catch criminals.

Question 10

What were the weaknesses of Lombroso’s theory?

Answer 10

He failed to compare his findings with a control group of non-criminals. This meant that he could have found that these features were just common in society at the time, and not a sign of criminality.

The research is scientifically racist: some of the features he described are linked to skin colour and can produce damaging stereotypes as to how people view certain demographics.

His theory of a born criminal is deterministic, arguing that people do not choose to commit crime. This could lead to people not taking responsibility for their actions as they felt they had to commit them.

Question 11

What is the main idea of Sheldon’s theory?

Answer 11

Links to Lombroso’s theory: the idea that criminal behaviour is linked to someone’s physical form.
He determined that individuals with a mesomorphic body type were predisposed to criminal activity.

Question 12

How did Sheldon conduct his research?

Answer 12

He studied a sample of photographs showing the front, side and back view of 4000 male college students and delinquents, rated on a scale of 1 (low) to 7 (high) their resemblance to the mesomorph body type.

He found that criminals had a higher average mesomorphic score (4.6) than the students (3.8)

Question 13

What are endomorphs?

Answer 13

People who are soft with a tendency to have more body fat and to lack muscle.

Personality= sociable and relaxed.

Question 14

What are mesomorphs?

Answer 14

People who are muscular and hard-bodied, with very little fat and broad shoulders.

Personality= active and assertive.

Question 15

What are ectomorphs(vECTOr)?

Answer 15

People who are thin and fragile, lacking fat and muscle. Flat chested, thin face, high forehead.

Personality= quiet, fragile, sensitive.

Question 16

What were the strengths of Sheldon’s theory?

Answer 16

He used a large sample of students (4000) and compared his findings with a control group. Large sample increases population validity and control group means he would have been able to see any large differences between criminals and non-criminals.

Other researchers have found results supporting his theory. Eg- Glueck and Glueck found in their sample of delinquents 60% were mesomorphs, while in a non-delinquent sample there were only 31% .

The most serious delinquents in Sheldon’s sample were the ones with the most extremely mesomorphic body shapes.

Question 17

What were the weaknesses of Sheldon’s theory?

Answer 17

He did not explain how ectomorphs and endomorphs can also commit crime- he does not provide a full account of criminal behaviour.

A person’s somatotype is not fixed and can change over time due to environmental factors such as diet and exercise. He does not discuss those who have stopped being a part of the mesomorph body type etc.

Mesomorphs may indulge in crime due to societal expectations. If someone is well-built, society may expect them to be more aggressive and involved in fights so they may do so: self-fulfilling prophecy. Sheldon does not take this into account.

Convicted offenders are mainly working-class males, who are more likely to be in manual jobs where they acquire an athletic build. Class may be a larger influence on committing crime.

Question 18

What are the 3 genetic studies?

Answer 18

Jacob’s XYY theory, twin studies, adoption studies.

Question 19

What was the overall idea of Jacob’s XYY study?

Answer 19

That abnormality of the sex chromosomes can cause criminal behaviour.

One abnormality could be an extra Y chromosome in men, labelled as the ‘super male syndrome.’ Occurs every 1 in 1000 male births and every 15 in 1000 male prisoners.

Men with extra Y chromosomes were seen as tall, well-built, with low intelligence and higher aggression.

Question 20

How did Jacob et al conduct his research?

Answer 20

They found 7 cases of XYY men in a study of 197 individuals in a mental hospital in Edinburgh.

Many of these men had histories of aggression and violent assault.

Question 21

What are the strengths of Jacob’s XYY study?

Answer 21

There has been supporting evidence for the theory. 1 study by Jacob et al. (1965) found that a significant number of men in prison had XYY sex chromosomes instead of the normal XY- this suggests that there is a link between XYY syndrome and criminal behaviour.

Other researchers have also supported the theory. Alder et al. (2007) indicated that it is possible that aggressive and violent behaviour is at least partly determined by genetic factors. This suggests that there could be a correlation between XYY chromosomes and criminal behaviour.

Question 22

What are the weaknesses of Jacob’s XYY srudy?

Answer 22

Studies found that genetic abnormalities are widespread throughout the general population and they are not just confined to prisoners. This is a weakness because it does not suggest that XYY syndrome has any effect on criminal behaviour.

Although there has been supporting evidence, there has also been evidence that refutes the explanation. Theilgaard (1984) researched the traits of XYY men compared to XY men. He found that the characteristic of aggression was not associated with the XYY me. This suggests that XYY syndrome has no bearing on aggressive behaviour and therefore, no link to crime.

The theory focuses too heavily on genetics and it ignores the potential influence of the environment. This is a weakness because it has been suggested that criminal behaviour is a result of an interplay between genetics and the environment and thus this is not a full explanation of criminal behaviour.

The symptom is very rare (1 in 1000) so cannot account for a lot of criminality.

Question 23

What is the overall idea of twin studies?

Answer 23

Investigating the influence of nature and nurture on criminal behaviour. Monozygotic twins share 100% of their genes and 100% environment. Dizygotic twins share 50% of their genes and 100% environment. If there is a higher concordance rate between monozygotic than dizygotic twins, we can assume criminality is genetic.

Question 24

How were twin studies conducted?

Answer 24

Christiansen studied 3586 twin pairs in Denmark. He found that there was a 35% concordance rate between MALE MZ twins; where one identical twin had a conviction, there was a 35% change of the other twin also having a conviction. But among non-identical MALE twins there was only a 13% chance.

Similar study by Ishikawa and Raine found a 44% concordance rate for identical twins but only 22% for non-identical twins.

Question 25

What are the strengths of twin studies?

Answer 25

Twin studies are natural experiments, as the biological relationships between the twins is a naturally occurring variable because researchers are not manipulating the variable themselves. This is a strength as it allows researchers to examine criminal behaviour in a way that would otherwise be unethical or impossible.

Similar study by Ishikawa and Raine found a 44% concordance rate for identical twins but only 22% for non-identical twins.

Supporting evidence for the use of twin studies. Christiansen (1977) conducted a study where 3586 twin pairs were examined, the concordance rate for MALE monozygotic twins was 35% whereas the concordance rate for dizygotic twins was 13%. This is a suggests that if one identical twin was a criminal, the other twin was 35% more likely to also be a criminal. The fact that concordance for DZ twins was 22% shows that there must be a genetic link.

Question 26

What are the weaknesses of twin studies?

Answer 26

Early twin studies were not controlled and due to this lacked validity- researchers in the 1920s would guess whether twins were MZ or DZ by appearance, rather than genetics. This is a weakness because researchers were often unsure whether the twins they were testing were MZ or DZ and therefore, the results could be meaningless.

The samples used are usually quite small meaning that twin studies may not be representative of the general population. This is a weakness because studies tend to lack population validity and be generalised back to the whole population.

Issue with the fact that twins are brought up in the same environment- criminality could actually be related to nurture, rather than genetics. Twin studies do not take the environment into consideration and assume that all behaviour is due to genetics. MZ twins do not have a concordance rate of 100% and therefore other factors must be involved.

Question 27

What is the overall idea of adoption studies?

Answer 27

Studies that compare adopted children to the biological birth parents and adopted parents. Adopted children do not grow up in the same environment as their biological birth parents and so researchers can see whether genetics or environment has more of an effect on crime and criminal behaviour.

Question 28

How were adoption studies conducted?

Answer 28

Mednick et al examined data on over 14000 adopted sons in Denmark. Found that sons were more likely to have a criminal record if a birth parent also had a criminal record (concordance rate 20%). They found that a smaller percentage (14.7%) had a record if their adoptive parent had one.

Hutchings and Mednick compared adoptees with and without criminal records. They found that adoptees with criminal records were more likely to have biological parents with criminal records than adoptees whose birth parents did not have criminal records.

Question 29

What are the weaknesses of adoption studies?

Answer 29

Age of adoption may mean that children have already been influenced by their birth parents- children can be taken from parents at any point before the age of 18. Weakness as any criminal traits could have already been learned from parents before the child was placed with someone else.

Information about a biological family is not always available- some adoptions are closed and some families do not consent to information sharing. Weakness as data cannot be gathered, and therefore we cannot draw links between parents and criminal behaviour.

Adoption process is not always random- often, children are placed with adoptive parents who are similar to their biological families. Weakness as the adoptive family may have similar values to the biological family and influence criminal behaviour in this way.

Question 30

What are the strengths of adoption studies?

Answer 30

Adopted children are exposed to a different environment to their biological parent- meaning that it is easier to separate genetic and environmental factors. This increases the validity of adoption studies as we can see clearly whether genetics or the environment has most effect on criminal behaviour.

Studies have concluded that there is a correlation between adopted children and their biological parent. Eg- it was found that if a biological mother had a criminal record, 50% of the adopted children had one by the time they were 18. Strength as it shows increased support for adoption studies and supports the fact that criminal behaviour is genetic.

Question 31

What does the prefrontal cortex in the frontal lobe do?

Answer 31

Important in monitoring and regulating our behaviour, damage to this area could cause behavioural problems.

Question 32

What does the amygdala do?

Answer 32

Important for the processing of emotions, particularly fear; It has been found that there are important differences in the activity in the left and right amygdala. If this area is damaged, an individual may feel less emotions so may be more inclined to commit crime.

Question 33

What is the overall idea of Raine’s brain study?

Answer 33

To identify the specific brain regions in 41 offenders charged with murder or manslaughter who had pleaded not guilty due to insanity.

Used a PET scan to highlight areas of brain activity and compared results to control group.

Question 34

What were the results of Raine et als brain scans?

Answer 34

Found reduced activity in areas like the prefrontal cortex of the offenders. Found abnormalities in the activity of the limbic system, including the amygdala.

Question 35

Describe the case of Phineas Gage relating to brain damage.

Answer 35

Railroad worker who survived an accident in which a large iron rod went through his head, destroying much of the left frontal lobe of his brain. Became extravagant, anti-social and started using bad language, which was different from his previous personality.

Question 36

What are the strengths of brain studies?

Answer 36

Certain extreme cases like Phineas Gage where brain injury or disease has led to major changes in personality including criminal behaviour.

Correlation between abnormal EEG readings and criminality.

Prisoners are more likely than non prisoners to have brain injury.

Question 37

What are the weaknesses of brain studies?

Answer 37

Brain disease/injury is rare. Personality is likely to be a more important factor.

Not clear that abnormal brainwave activity causes criminality. Some psychopathic criminals have normal EEG readings.

Prisoners higher likelihood of brain injury could be a result rather than a cause of their criminality - e.g. getting into fights.

Question 38

How can brain diseases be linked to criminal behaviour?

Answer 38

In 1920’s, there were epidemics of encephalitis lethargica among children which refers to the swelling of the membrane around the brain which can cause damage to the brain. The children were more impulsive and destructive.

Question 39

What is the role of sex hormones for men in biochemical explanations?

Answer 39

Men have much higher levels of testosterone than women: Ellis and Coonitz found a correlation between testosterone peak levels and age for highest crime rates in males.
Steve Jones stated that men injecting testosterone/ steroids had a higher death rate from violence and suicide.

Question 40

What is the role of sex hormones for women in biochemical explanations?

Answer 40

PMT, postnatal depression and lactations all alter the hormone levels in a women’s body so have been accepted as partial defences for women charged with crimes due to the fact that they change someone’s judgement, mood, self control.

Question 41

What is the role of neurotransmitters in biochemical explanations?

Answer 41

Low levels of serotonin (chemical which regulates mood) have been associated with mental health disorders like OCD, PTSD, anxiety and people with these disorders may be more likely to commit crime.

Low levels of tryptophan (an amino acid) may also be linked to aggression: can increase the levels by eating more protein-rich foods.

Question 42

What is the role of blood sugar levels in biochemical explanations?

Answer 42

Hypoglycaemia (low blood sugar levels) can trigger aggressive reactions.

Link between low blood sugar levels and alcohol abuse: large quantities of alcohol can induce hypoglycaemia which can cause depression.

Question 43

What is the role of substance abuse in biochemical explanations?

Answer 43

Saunders- alcohol plays a significant role in around 1000 arrests a day in the USA.

Flanzer- estimated around 80% family violence cases involved alcohol.

Question 44

What are the strengths of biochemical explanations of criminality?

Answer 44

Recognised by courts: eg if woman kills her baby due to post-natal depression or breastfeeding, she has a partial defence to murder ‘law of infanticide’

PMT accepted as defence to shoplifting.

These factors could lead to possible treatment methods- eg decreasing prisoners’ sugar intake.

Question 45

What are the weaknesses of biochemical explanations of criminality?

Answer 45

These explanations may predispose some individuals to offend, but may require an environmental trigger to offend.

Individual differences such as personality mean some people react different to chemicals.

Rate of testosterone declines with age more slowly than the rate of offending.