Biological Explanation For Criminality - Inherited Criminality Flashcards
Twin study
Concordance rate of criminal behaviour
Rosanoff et al - MZ has 67% concordance rate, DZ 13%
Raine + Ishikawa - meta analysis 44% Mz, 22% dz
Suggest there is genetic disposition, since more closely related twin higher chance to have criminal behaviour
Dalgard + Kringlen- MZ concordance 24%, suggest MZ + dz not matter
Family study
Osborn + West - 13% of son with non- criminal father had criminal record, 40% of son did have criminal dad
Farrington - looked at 3 generations of relatives (grandad, uncle, son) of one is arrested high chance another will be arrested. If father arrested highest chance of son also arrested
-young mother + bad neighbourhood more chance of father + son arrested
Adoption studies
Mednick et al - 25% of adoptive son have criminal record with biological criminal dad, 15 of adoptive son have with no bad dad
Role of gene
Raine - Brain images of murderer, psychopaths + violent individual. Reduced functions in prefrontal cortex. Causes impulsiveness + loss of control.
Reif et al - NOS1 gene has link with aggressive behaviours. Aggression can cause type 1 murderers as can’t control self or sexual offenders who enjoy harm on others.
Tiihonen et al - link of irregular MAOA gene linked with criminal behaviour. Since this gene control recycle of serotonin
Seo et al - low level of serotonin cause impulsive + aggressive behaviour. If individual is poor, make them more likely to be an acquisitive criminal as can’t control stealing.
Diathesis stress model
Gene require environment for switch
Epigenetics- gene for disorder can be switched on + off
Caspi et al - 12% of men with low MAOA gene who experienced maltreatment responsible for 44% of violent convictions in study
Evaluation - Causal relationship can be found
Tiihonen et al - link of irregular MAOA gene linked with criminal behaviour. Since this gene control recycle of serotonin
Seo et al - low level of serotonin cause impulsive + aggressive behaviour. If individual is poor, make them more likely to be an acquisitive criminal as can’t control stealing.
Concordance rate Rosanoff et al to show why relative have criminal behaviours
Clearly states the reasons why irregular gene or being related can cause someone to be or more likely to commit crimes. Can be used in raising awarness or therapies to ensure people with these factors does not commit crime
Evaluation - Most studies on inheritance are based on heritability study
-Family+ twin studies - shared environment, so cannot solely be genes when it might be environment that causes it. Twin study MZ treated the same, so if an upbringing cause a sibling to be criminal, other will have same upbringing.
-Twin + adoption study - not much sample size in uk only 1.5% DZ, 0.5 MZ in Britain, less studies conducted to compare = less reliable
-Focus on gene too much, Farrington - families with young mother + bad neighbourhood increase chance of dad + son arrested
Evaluation - not ethical
If finding potential criminal becomes the norm. Can invade personal privacy if forced to get brain scan. James Fallon, he has genes make him more likely to be a criminal but good upbringing cause him to be good. Can cause unnecessary stress on normal people.
Overall
heritability study is useful to be used to explain why certain people are more likely to commit crime by genes or relatives. But more variety of researches aside from heritability study needed to avoid methodological issues to increase validity of this explanation. As well as more concrete research is needed on how genes can cause criminal behaviours to not cause unnecessary public discord.
