FORENSIC - BIOLOGICAL EXPLANATIONS FOR OFFENDING BEHAVIOUR

HISTORICAL APPROACH (ATAVISTIC FORM)

  • idea offenders may represent more primitive evolutionary stage of development than their contemporaries - shown through 'ativistic' features.
  • LOMBROSO measured physical features of italian criminals and argued their measurements distinguished them from non-criminals. e.g. heavy brows, large strong jaws, large ears, extra nipples/fingers/toes. -> demonstrated they were from earlier evolutionary stage of development & criminals are born this way.

❌ GORLING - compared 2348 London convicts w control group. failed to replicate it. -> criminal behaviour not linked to physical appearance.

❌ METHODOLOGY ISSUES - Lombroso's findings rejected.

❌ SICILIANS ONLY - known to have different physical appearances to Italians/non-Italians = not generalisable.

❌ some CRIMINALS MENTALLY ILL - may affect their appearance

GENETICS

NEURAL EXPLANATION

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✅ TWINS TUDIES: CONCORDANCE HIGHER WHEN GENETICALLY MORE SIMILAR. - supports idea of genetic transmission.
❌ MZ TWINS TREATED MORE SIMILARLY to each other than DZ twins. -> could account for increased rate of concordance.

❌ STRESS OF ADOPTION - may account for offending behaviour in adopted children.

❌ DOESN'T MEAN ITS DUE TO GENETIC TRANSMISSION - could be SOCIAL LEARNING or ENVIRONMENTAL influences.

ADOPTION STUDIES - meta analysis of 51 twin and adoption studies was conducted to extimate extent of environmental and genetic influences on anti-social behaviour.

  • strength of family influences was lower in parent-offspring adoption than in both twin + sibling adoption studies, suggesting a genetic link.

FAMILY STUDIES: FARRINGTON - 411 males living in London from 400 families were monitored from age 8-32 (interviews). from 10-40 in crime records. - conviction rates of these men compared to conviction rates of their biological parents/family.

  • found 64% of families had at least one convicted person.
  • 75% of convicted fathers and mothers had a convicted child.

BIOCHEMISTRY

  • NORODRENALINE:


    part of fight or flight response high levels associated w/ violence/ aggression- explains some crimes undermined by chemical imbalance


  • SEROTONIN:


    Regulates your mood and impulse behaviour , crimes are committed under highly emotional states., high levels cause violent and aggressive due to absence of MADA enzymes

  • DOPAMINE:

    Strongly linked to addiction and feeling pleasure from it. The greater the activity, the greater the feeling of pleasure - more addictive

  • ✅ Higley -

    Found levels of testosterone to be positively correlated w/ aggressiveness but not impulsivity.


    Levels of serotonin is negatively correlated w/ impulsive behaviour & extreme aggression but not general aggression.


    Study done on non human primates and suggested that biochemical levels link to some aspects and offending behaviour.

❌ ANIMAL RESEARCH - invalid, cannot be generalised to humans.

❌ BIOCHEMICAL EXPLANATION: REDUCTIONIST - too simplistic/simplifying criminal behaviour - issue us more complex in individual's brain.

BRAIN PHYSIOLOGY

LIMIBIC SYSTEM:

  • central part of the brain, ‘the primitive area’
  • centre where emotions are modulated.-criminals may have problems processing emotions& empathy- lack of remorse/guilt & are more self serving as a consequence.

BRAIN DEVELOPMENT

  • centred around individuals w/ anti social personality disorder
  • RAIN et al- suggested frontal lobe volume of people w/ antisocial personality disorder is less than those without disorder
    — suggests this might be why they feel a lack of guilt over their actions as they cannot process information correctly concerning consequences of their actions.

✅ RAINE -

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