biological theories

• LOMBROSO


  key idea = criminals are biological are different from non-criminals

  study = measured 400 dead criminals heads and faces

  findings = criminals where more likely to have large jaws, arms, and aquiline noses

  atavism = criminals are throwbacks to primitative stage of evolution - presocial, impulsive, reduced sensitivity to pain
• evaluations of lombroso

  strengths

  1. first scientific study of criminology
  2. shows importance of clinical and historical records of criminals
  3. focuses on prevention not punishment
• evaluations of lombroso

  limitations

  1. no further evidence to like facial features with criminality
  2. did not use a control group
  3. racist ideas that links criminals with non-western societies
• SHELDON

  key idea = body types can be related to criminality

  study = looking at body types and comparing them to the likelihood of committing criminal offences

  findings = mesomorphic somatypes where most likely to be criminal

  as they are attracted to risktaking, and their physique (muscular, strong limbs, broad shoulders) is important to their behaviour.
• evaluating sheldons somotypes

  strengths

  1. other studies have replicated the findings
  2. the most serious delinquents had mesomorphic body types
• evaluating sheldons somotypes

  limitations

  1. criminality likely to be a combination of biology and environment
  2. the mesomorphic build may be a result of criminality
  3. social class could have a factor in criminality and somotypes
  4. mesomorphs more likely to be labelled
• actavism - the idea that criminals are "throwbacks" to a more primative stage of evolution
• endomorph - rounded, soft bodies, lacking muscle, sociable, relaxed and outgoing
• ectomorph - thin, fragile, lacking fat and muscle, flat chested, narrow hips and shoulders, thin faced, self conscious, emotionally restrained and thoughtful
• mesomorph - muscular, little fat, strong limbed, broad shoulders, narrow waist, adventurous, assertive, dominant
• physiological theories - sheldon + lombroso. claim that physical features of criminals differ from non - criminals
• biological theories - criminals are biologically different from non - criminals and this causes them to commit crimes
• genetic theories - twin and adoption studies + jacobs XYY theory. criminality is the result of genes inherited from the biological parents (supports the nature debate)
• christiansens twin studies 


  key idea = if crime is genetic, identical (monozygotic) twins should have identical criminal behaviour

  study = 3,500 twin pairs in Denmark

  findings = concordance of 52% for MZ and 22% for DZ
• Mednick et al adoption study

  key idea = adoptees share the environment of their adoptive parents but the genes of their biological parents. if crime is genetic they would follow the criminal trends of their biological parents

  study = 14000 Danish men born between 1924 and 1947 

  findings = concordance between birth parents - 20% VS adopted - 14.7%
• evaluating twin and adoption studies

  strengths

  1. give some support for genetic explanations of criminality
  2. adoption studies overcome the problems with isolating genes and environments
  3. logical research designs
• evaluating twin and adoption studies

  limitations

  1. Mednick et al only studied men
  2. if criminality was solely genetic the concordance rate for MZ twins would be 100%
  3. impossible to completely isolate genetics and environments/
• JACOBS XYY


  key idea = XYY syndrome makes males genetically predisposed to criminality

  study = compared rates of XXY in imprisoned criminals and general population

  findings = on average there was a higher proportion of inmates with the syndrome
• features of XYY = very tall, well - built, low intelligence, high aggression
• evaluation of Jacobs XYY

  strengths

  1. found association between aggressive prisoners and XYY syndrome
  2. price and watmore - supported a link between XYY and property crime
• evaluating Jacobs XYY

  limitations

  1. not everyone with XYY was a criminal and not every criminal had XYY
  2. only theorises based on criminality in males
  3. alligns with labelling theory
  4. the low intelligence may be the reason for higher percentage of XYY in prisons
  5. syndrome is too rare to explain criminality as a whole
• monozygotic - identical twins

  dizygotic - non - identical twins