biological theories of criminality

Question 1

what are some examples of biological theories?

Answer 1

-lombroso’s born criminal theory
-sheldon’s somatotypes theory
-jacob’s xyy theory
-twin studies
-raine
-lange
-christenson
-adoption studies: mednick
-bowlby’s maternal deprivation theory

Question 2

what is lombroso’s born criminal theory?

Answer 2

-born criminals can be determined by the facial features and body
-they are atavistic and primitive
-atavistic: unable to control impulses, reduced sense of pain (tattoos, piercings)
-e.g., long arms, enormous jaws, sunken eyes
-studied 383 dead criminals and 3839 alive ones: 40 offenses could be accounted for
-could determine what crime was committed by looking at them
-murderer’s have an aquiline nose

Question 3

evaluation lombroso’s theory

Answer 3

strengths
-charles goring (2013) found that criminals had lower intelligence than those who weren’t offenders, suggesting a genetic link
weaknesses
-extremely deterministic theory: not everyone who has atavistic features will commit and vice versa

Question 4

what is sheldon’s somatotype theory?

Answer 4

-three body types
-ectomorph: thin, fragile, restrained socially; least likely to commit
-endomorph: fat, soft, relaxed, sociable
-mesomorph: hard, muscular, domineering, adventurous; most likely to commit
-analyaed 4000 different bodies from several angles, conluding there were three types

Question 5

evaluate sheldon’s theory

Answer 5

strengths
-gleuk and gleuk found 60% of delinquents were mesomorphs and 31% non-delinquents were mesomorpbs
weaknesses
-body type is not fixed overtime
-bias in the judicial system

Question 6

what is jacob’s xyy theory?

Answer 6

-criminality is due to chromosome abnormality
-xyy chromosome = supermale
-only men
-not heritable, cannot be transferred onto children or from parents
-random error in formation of sperm of embryo
-supermales are well-built, agressive and of low intelligence
-studied imprisoned criminals in psychiatric prisons
-1/1000 general public are supermales
-15/1000 psychiatric criminals are supermales

Question 7

evaluate jacob’s xyy theory

Answer 7

strengths
-john wayne gacy: 33, 29 in home, rest in river, 14 the youngest
weaknesses
-female criminality???
-external factors

Question 8

what are concordance rates?

Answer 8

the rate of possibility that two people who share the same genes will both develop offending behaviour

Question 9

what did raine study?

Answer 9

-delinquent teens
-used a pet scan and found that delinquent teens had less brain activity in the grey matter of their prefrontal cortex
-serotonin is the hapoy neurotransmitter in charge of emotions and mood regulation
-low levels of serotnin = agression
-excessive exposure of serotonin in the womb = desensitisation in later life

Question 10

what did johannes lange study?

Answer 10

-investigated 13 MZ twins and 17 DZ twins
-found 10/13 MZ twins were in prison
-2/17 DZ twins were in prison
-suggests that MZ twins are more likely to reoffend as they both share a higher percentage of genes than DZ twins (concordance rates are higher)
-may have inherited the sams criminal gene
-lange also examined 30 male prisoners and found that 52% of MZ twins had a criminal brother
-12% of DZ twins had a criminal brother

Question 11

what did christenson study?

Answer 11

-studied 3,500 twins in denmark
-the concordance rates in men were 32% for MZ twins and 12% for DZ twins
-the concordance rates in women were 21% for MZ twins and 8% for DZ twins

Question 12

what are twin studies?

Answer 12

-compares an identical, single egg (MZ) and a non-identical, double egg (DZ)
-DZ twins are born at the same time but come from two separate eggs sharing 50% of DNA
-MZ twins are born at the same time but share the same egg, sharing 100% of DNA

Question 13

evaluate twin studies

Answer 13

strengths
-there are multiple supporting studies from lange, christenson, and raine
weaknesses
-enviornmental factors?? twins share the same enviornment so criminality may not be down to genetics

Question 14

what are adoption studies?

Answer 14

-where adopted children are compared to their biological and adopted parents to see which one had more of an influence: biology or envionrment?

Question 15

what did hutchings and mednick study?

Answer 15

-studied 14,000 adopted children
-found a high proportion of boys with criminal convictions have biological parents with one too
-no relationships between criminal convictions in adopted chilren and adopted parents
- found sons were more likely to have a criminal record if biological parent had one: concordance rate of 20%
-14.7% had a criminal conviction if their adoptive parent had one

Question 16

evaluate adoption studies

Answer 16

strengths
-large sample of mednick’s study: more valid to society (highly generalisable and high high population validty)
weaknesses
-adopted children may have been adopted similar to their biological enviornment/ circumstances: not always random adoption
-age of adoption: those adopted later (e.g., 7 years old) may have already been influenced by their biological enviornment

Question 17

what is bowlby’s maternal deprivation theory?

Answer 17

-there is a link between maternal deprivation and deviant behaviour
-a child needs a close relationship with a pcg (normally mother) in order to develop normally
-if separated even for a short time, the child can form attachments with other, leading to affectionless psychopathy or criminal behaviour
-bowlby studied 44 thieves: 39% had suffered maternal deprivation before the age of 5 compared to 5% of a contr group of non-delinquents

Question 18

evaluate bowlby’s maternal deprivation theory

Answer 18

strengths
-control group to compare to
-bowlby’s 44 theives - 39% of criminals were deprived maternally compared to 5% of non-criminals who were
weaknesses
-overly deterministic theory: not everyone who was deprived maternally will turn to crime and vice versa