Forensic Psychology

• 3 main goals of offender profiling

  • Social and psychological assessment: basic info e.g., personality, sex, race, employment
  • Psychological evaluation of belongings: possessions associating offender with crime scene e.g. souvenirs, photos
  • Interviewing suggestions and strategies: techniques suitable for individual offenders e.g. being trendy
• The Top-Down Approach


  1. Interview based technique: US based conducted by FBI

  2. Began in 1970s, FBI conducted in-depth interviews with 36 sexually motivated murderers inc Ted Bundy and Charles Manson to find why/how they committed crimes concluding that data could be categorised into organised/disorganised crimes

  3. If data from crime scene matched a category, we can generate other likely characteristics to narrow down suspects
• Organised Offender


  • Evidence of planning at crime scene as victim's deliberately targeted so killer has 'type' of victim they seek out
  • High degree of control maintained
  • Above avg intelligence in skilled profession
  • Socially/sexually competent + may be married W kids
• Disorganised Offender


  • Little evidence of planning – spontaneous
  • Low than avg IQ in unskilled work
  • Sexually/socially dysfunctional with failed relationships
  • Tend to live alone + lives close to crime scene
  • Low level of control
• Organised Crime Scene

  Little evidence of clues left behind
• Disorganised Crime Scene

  Reflects' impulsive nature, body's still at scene
• The Process of Offender Profiling

  1. Data assimilation: Info gathered from crime scene + other sources on exactly what happened

  2. Crime scene classification: Decision made re whether criminal appears to be organised and planned or acted hastily in an unplanned way

  3. Crime reconstruction: Hypotheses generated on what may've occured in crime scene e.g. victims behaviour/events

  4. Profile generation: rough 'sketch' developed inc social grp, appearance or likely behvaioural traits
• The Bottom-Up Approach


  1. Aim: generate pic of offender and their likely characteristic, behaviour and social background by systematic analysis of evidence at crime scene

  2. Techniques used: Investigative Psychology, Geographical Profiling
• Investigative Psychology


  Applies statistical procedures to analyse crime scene evidence so general behaviour patterns are established across crime scenes so statistical database can be used as a baseline for comparison
• Geographical Profiling

  • Uses info on crime locations for inferences on likely basis of offender
  • Known as crime mapping and based on spatial consistency: people committing crimes in a limited geographical space
  • Can be combined with investigative psych to create hypotheses
• Canter's Circle Theory


  • Assumption that serial killers offend in familiar areas so understanding their behaviour patterns provides a centre of gravity (circle) around offender base
  • Offenders commit crimes in 2 ways: Marauders (proximity to home, hide identity) and Commuters (travels distance away from home w/o hiding identity but around area of some familiarity)
• In the 1870s, Italian doctor Cesare Lombroso wrote a book 'the criminal man' which suggested criminals were a more primitive version of humans
• Atavistic Form

  • Criminals were less evolved and were a genetic throwback to less advance human forms and so aren't evolved enough to live in civilised society
  • Criminal 'types' can be identified by looking at physical characteristics
• Common characteristics found in criminals by Lombroso

  • Narrow, sloping forehead
  • Strong heavy jawline
  • Large protruding ears
  • High cheekbones
  • Long, pointy nose
  • Extra nipples
  • Insensitive to pain
  • Tattoos
  • Unemployment
• Lombroso's work questioned if criminals are born or made, suggesting crime has a biological explanation and is genetically determined
• Genetics and Crime


  • No single criminal gene identified, but several genes that are linked to inc offending behaviour such as low activity MAOA gene and CDH13
  • Earlier evidence from twin, adoption and family studies found criminal behaviour to run in families and more closely related you are to a criminal, more likely you'll be one
• Research by Tihonen found people in the sample who had both the low activity MAOA gene and CDH13 gene were 13x more likely to commit multiple violent offences
• There was no baseline to which the comparisons could be made
• Genetics


  Suggests criminals may inherit genes which make them more likely to commit crimes. No single criminal gene identified, but several genes that are linked to increased offending behaviour
• Low activity MAOA gene


  • Controls activity of dopamine and serotonin in the brain linking to aggressive behaviour. Called 'warrior gene' as links to violence
• CDH13


  • Increases likelihood of ADHD and substance misuse
• Research by Tihonen found people in the sample who had both the genes were 13x more likely to commit multiple violent offences
• Earlier evidence from twin, adoption and family studies found criminal behaviour to run in families and more closely related you are to a criminal, more likely you'll be one
• Lange found that MZ twins in prison were more likely to have a co-twin who'd also been in prison compared to DZ twins. As MZ twins have 100% of their genes in common, but DZ twins only have 50% of the same genes, suggesting genetics plays a role
• Brunner (1980s) studied a Dutch family finding many of its males behaved in a violent/aggressive way and many were involved in serious crimes of violence including rape and arson. Men found to have deficiency of MAOA warrior gene leading to Jekyll and Hyde behavioural reaction
• The study by Brunner is guilty of gender bias as it was only on males so inappropriate to generalise the genetic theories to females
• The unusual aggressive behaviour in the Dutch family could be argued to now be an expectation so these acts are accepted, and behaviour could be due to environment (social learning theory) rather than biological reasons
• In the Irish travelling community, males are taught to be strong and fight but this doesn't mean it's due to biological reasons but due to how they're nurtured
• Assuming someone who has the criminal gene will be a criminal is a form of biological determinism which predicts those who have the gene will be a future criminal
• Our justice system is based on the idea that criminals act with free will and take responsibility for their actions after the event not before
• There is an ethical issue with biological determinism because we do not currently have any way to successfully help those at risk of becoming a criminal in the future or protect society from them
• If we can predict a high level of the presence of MAOA genes in certain areas, we can put into place educational programmes that can help prevent their gene from coming into play
• Antisocial personality disorder (APD)


  Associated with reduced emotional response, lack of empathy for other feelings and is present in many offenders
• Raine conducted many studies of a APD brain, reporting that scans showed decreased activity in pre-frontal cortex which regulates emotional behaviour. He found an 11% reduction in the volume of grey matter in the prefrontal cortex in those with APD compared to controls
• Recent research found that offenders with APD can experience empathy but just less compared to someone without it
• When offenders with APD were asked to empathise (with someone on a film feeling pain), their empathy reaction did activate, suggesting that offenders with APD do have empathy but may have a neural switch that's turned on/off unlike normal brains which have it continually on
• Kandel and Freed reviewed evidence of frontal lobe damage (including prefrontal cortex) and antisocial behaviour and found that those with damage tended to show antisocial behaviour, emotional instability and inability to learn from mistakes which are characteristics of offenders
• The research by Kandel and Freed was correlational so cannot establish cause and effect between brain and offending as there may be a third variable e.g. poverty that may actually be the causal factor
• Using a small, simple experimental finding like reduced activity in the prefrontal cortex underemphasises the complex and diverse reasons why people commit offences, which may mean that schemes can't be developed to help counteract/prevent offending behaviour
• Eysenck's theory of criminal personality


  He developed a theory measuring 3 dimensions: introversion/extroversion, neuroticism/emotional stability, and psychoticism