Describe Biological Theories of Criminality (AC 2.1) Flashcards
What are the 4 main biological theories of criminality?
Physiological theories
Genetic theories
Brain injuries and disorders
Biochemical theories
Physiological Theories
Focusing on physical characteristics, they claim that the physical features of criminals differ from those of non-criminals
Physiological Theories - Lombroso: Born Criminals
Lombroso concluded that criminals can be identified by their distinct physical features, examples of features he found while studying criminals are: High cheekbones, long arms, acute eye sight, extra toes/ fingers, etc… He explained these traits through Atavism.
Atavism
Relating to something ancient or ancestral. Lombroso explained criminals as throwbacks to a more primitive stage of evolution, they were pre-social, had a higher pain tolerance and were unable to control their impulses. Criminals are like savages, more similar to apes, thus they are abnormal in a modern society.
Physiological Theories - Sheldon: Somatotypes
Sheldon explained that a certain body type was linked to criminality, mesomorph. Mesomorphic body types are much more muscular and more likely to act aggressive. This is what makes them much more likely to be involved in crime, the enjoy engaging in risk-taking activities that involve their imposing physique.
What are the three Somatotypes?
- Ectomorph, thin and fragile: introverted and restrained
- Endomorph, fat and soft: sociable and relaxed
- Mesomorph, Muscular and hard: aggressive and adventurous
Genetic Theory
Criminality is inherited, criminal genes are passed down from parent to child which is why crime runs in families
Twin studies
Twin studies measure the concordance rates between Monozygotic and Dizygotic twins to determine if criminality is caused by genes and if monozygotic concordance rates are higher we can concluded it is (100% concordance would mean it is directly caused by genes)
Genetic Research - Christiansen
In his study of over 3000 twin pairs the concordance rates for identical twins was 52% and it was 22% for non-identical twins
Adoption studies
Adoption studies compare adopted children to their birth and adoptive parents, if their behaviour is similar to their biological parents rather than adoptive this would suggest a genetic explanation
Genetic Research - Mendick
Mendick examined data of 14,000 adopted sons from Denmark and found that sons were more like to have a criminal record if their biological parents did (20%) than if their adoptive parents did (14.7%)
Concordance rates in criminology
A statistical measure that describes the proportion of a pairs that share a criminal history given that at least one already possesses the trait, 100% concordance would mean if one was criminal there’s a 100% chance the other is too
Genetic Theory - Jacob
Jacob’s XYY theory suggests that men who have an extra Y chromosome tend to be more aggressive and violent than other males making them more likely to be criminals, and it has been found that 15/1000 prisoners do have XYY syndrome compared to 1/1000 of the general population
Genetic Research - Price and Whatmore
Price and Whatmore found that men with XYY syndrome tend to be immature and unstable with a strong tendency to commit seemingly motiveless property crimes
Brain injuries and disorders
Certain injuries, diseases and malfunctions of the brain have been linked to causing criminality
Brain injuries explanation
In some rare cases brain injuries can be identified as the cause of criminality, certain studies show criminals to be more likely to have a brain injury then non-criminals
Example of a brain injury causing a dramatic change in personality
Phineas Gage had his entire personality change after a major injury to his fontal lobe, he was describe as much more irritable and aggressive after the fact
Brain disease explanation
Certain brain diseases (senile dementia, brain tumours etc.) have been linked to criminality, destructive, impulsive behaviour as well as arsonist and abnormal sexual activities. Abnormal brainwaves have also been measures amongst criminals
Biochemical Theory
Looking at biochemical processes and substances, such as hormones, brain chemistry has been linked to possibly cause criminal behaviour
Biochemistry linking to criminality - Sex Hormones
Male’s high testosterone levels have been show to increase aggressive behaviour and they peak from teen years to 20’s - correlating with crime rates
Female’s lactation and PND can be used as partial defences as the hormones effect judgment and control
Biochemistry linking to criminality - Blood Sugar Levels
Hypoglycaemia can trigger aggression, studies show a link between low blood sugar and alcohol abuse, drinking in large quantities is likely to increase crime
Biochemistry linking to criminality - Substance Abuse
Taking drugs is calculated to play a significant role in violent behaviours and arrests
Biochemistry linking to criminality - Other Substances
Things such as lead, sugar and synthetic food colouring have been linked to hyperactivity and Vitamin B. deficiency had been linked to erratic and aggressive behaviour
