Criminal behaviour - Biological - Inherited Criminality Flashcards
What is inherited criminality?
Inherited criminality involves the theory that crime occurs because of genetic predisposition that is passed down from their parents.
A gene that is potentially linked to Criminality is called a ‘candidate gene’.
What is the first element of Inherited Criminality?
The first element looks at the role of the MOA-A gene.
This gene produces the enzyme Monoamine Oxidise-A, this enzyme metabolises serotonin in the brain.
How does the MOA-A gene explain criminality?
A variant of the MOA-A gene produces less of the enzyme, this results in much higher levels of serotonin than usual
however because of this, over time the brain becomes desensitised to the calming effects of serotonin, this results in increased aggressive and therefore increased likelihood of criminal behaviour.
Name and describe the key study that is used to support the role of MOA-A in causing criminality?
Key Study – Brunner et al 1993
Study on large family in the Netherlands on a large family in the Netherlands where the men had a history of very violent crimes (rape and attempted murder)
In the study they analysed the X chromosome of 28 of the men in the family who were found to have a gene variant that resulted in particularly low levels of the MOA-A gene as well as lower levels of intelligence (average iq was 85). This gene was also not present in the non-violent men of the same family.
What is the second element of Inherited Criminality?
Twin Studies
Two types of twins:
Identical (monozygotic) share 100% DNA ———- Non-identical (dizygotic) share 50% DNA.
Using MZ and DZ twins, we can get a view into how much of an impact genes play in criminality using concordance rates. If MZ twins have a higher concordance rate than DZ twins we can infer that genetics play a part in that characteristic.
Name and describe the key twin study that is used to support the role of genes playing a part in criminality.
Key Study: Christiansen 1977
Involved the study of 3500 twin pairs in Denmark.
Compared the Criminal concordance rate between MZ and DZ twins by the time they turned 18 years old.
Results found MZ twins to have a significantly higher concordance rate than DZ twins implying a genetic element to criminality
Male MZ: 35%
Male DZ: 13%
Female MZ: 21%
Female DZ: 8%
What can we infer from the results of Christansen?
These findings are interesting as they indicate a degree of inheritance; however, there are some key points to consider. Firstly, the concordance rates are low, even for monozygotic twins, which indicates that the environment / Nurture still plays a large part in criminal behaviour.
Secondly the difference between male and female twin pairs raises an interesting question about the role of gender in criminal behaviour
What is the third element of inherited criminality?
Adoption Studies:
A key criticism raised by research into genetics (twin and family) is that it cannot rule out the effect of the environment. For example, a twin study may find a high concordance between monozygotic twins, but we don’t know how much of that is due to them growing up in the same environment.
Adoption studies attempt to rule this factor out by looking at children who have been adopted and have therefore been raised by adopted parents where there is no genetic similarity.
What key adoption study is used to support the role of inherited criminality?
Key Study: Crowe (1972)
This study involved a control and experimental group of all adopted children.
The experimental group had bio mothers who had a criminal record while the control group’s bio mothers did not.
The experiment looked at what portion of these children had a criminal record by age 18. in each group
They found 5% of control group had criminal record by 18.
While 50% of experimental group had criminal record by 18
What are the two strengths and weaknesses of inherited criminality?
Method of Mod
Research Evidence
Reductionist
Determinism and ethical implications
Name a strength of inherited criminality
1) Method of modification
This explanation suggest that some people commit crime due to a genetic predisposition e.g., a variant of the MAO-A gene has been linked to aggression which may lead to violent crime.
Therefore, a method of modification for criminal behaviour should involve altering a person’s genetic composition so that undesirable traits (such as aggression) are eradicated.
For example, by using genetic engineering, a defective MAO-A gene could be replaced with a ‘normal’ one in a fertilised ovum. This would then reduce the likelihood of aggression and violent criminal behaviour which could have huge benefits for society such as safer society and economic benefit.
Name a strength of inherited criminality
2) Research Evidence
Research evidence in the form of Crowe et al supports the view that criminality is inherited, Crowe is an adoption study meaning there is no element of nurture from the criminal parent and the only link is purely genetic.
Therefore the results showing that those with criminal biological mothers were 10x more likely to have a criminal record by 18 years of age shows a clear link between genetics and criminality and supports the idea that criminality is inherited rather than being developed by our surroundings.
Name a weakness of inherited criminality
Reductionism
With our modern understanding of genetic influence on criminal behaviour, research no longer suggests that our behaviour is determined solely by one or a few genes.
For example, A Diathesis-Stress explanation considers how the environment interacts with a genetic predisposition. suggesting criminal behaviour may be the result of a combination of both nature and nurture
Epigenetics, refers to the idea that genes we inherit from our parents can be ‘switched on or off’ through our experiences / environment.
For instance, someone has a criminal gene, but this gene is only activated due to a negative experience like a poor upbringing. This idea is supported in Capsi et al (2002).
This study looked at males from birth until 26 years old and studied their engagement in Criminal Behaviour.
It looked at the involvement of both the MOA-A gene as well as maltreatment during childhood.
Found that those who experienced BOTH the ‘low MOA-A’ gene and maltreatment were far more likely to engage in criminal behaviour than just the low MOA-A gene without childhood maltreatment.
Name a weakness of inherited criminality
2) Ethical Implications and Determinism
Determinism – lack of responsibility.
If criminal behaviour is truly caused by solely biological factors, it would suggest we cannot hold people responsible for their own actions and that it would be unethical to punish criminals as their behaviour was caused by physiological forces beyond their control.
Ethical implication - Racism
Another Ethical concern that could come as a result of this is racism, as some ethnic groups are more likely to be arrested than others, it could lead to a belief that those ethnic groups are ‘inferior’.
Ethical Implication – Gene eradication.
Lastly, on an extreme level it could result in attempted eradication of these genes deemed to be ‘criminal’ this has happened in the past where criminals were sterilised to prevent them from passing down the ‘criminal genes’ to their children
