Forensic psychology

• What Is Offender Profiling?

  Offender profiling is used to help find suspects. It involves forensic,

  physical and behavioural evidence.
• What is the aim of offender profiling?

  the overall aim is to help the police to narrow the field of

  investigation. The profiler is helping to put a personality to the

  offender and his/her motivations for committing the crime
• why is the American approach called ‘top-down’?

  it is called ‘top-down’ because it builds a classification system

  using information that is already known (i.e., interviews with known

  criminals) together with a behavioural analysis of crime scenes and

  information from victims and witnesses
• The British Approach – ‘Bottom-up’ Approach what was it?

  David Canter is the profiler most commonly known within the UK.

  He began working as a profiler in order to help the police in 1985

  when they were looking for a serial rapist (the ‘Railway Rapist’) –

  see case study below. The profile Canter provided described the

  rapist and where he lived with astounding accuracy.
• Why is the British approach called ‘bottom-up’?

  The British ‘bottom-up’ approach, according to Boon and Davies

  (1992), involves working with detailed information gathered from

  the scene of the crime and from information about the crime
• what is corpus delicti?

  CORPUS DELICTI – the ‘body of crime’

  The facts! Evidence that show a crime has taken place (e.g.,

  fingerprints, broken windows, ransacked rooms, missing items,

  victim’s blood, weapon)
• what is modus operandi?


  MODUS OPERANDI – the method of operation used by the criminal

  All the actions and behaviours that were needed to commit the

  crime
• what are the stages of topdown?

  data assimilation

  crime scene classification

  crime reconstruction

  profile generation
• Top down - 1. data assimilation

  • information is gathered from the crime scene about exactly what happened.  They will look at photos of the scene, forensic evidence, police reports etc.​
• Top down - 2. crime scene classification

  • Crime scene classification​
  • A decision is made regarding whether the criminal appears to be organised or disorganised.​
• Top down - 3. crime reconstruction

  • Hypotheses are generated about what probably happened during the crime scene. e.g. victim behaviour and the sequence of events.​
• Top down - 4. profile generation 


  A rough 'sketch' of the criminal is developed including social groups, appearance and likely behavioural traits.
• bottom up profiling- what are the two types?

  1. Investigative psychology​
  2. Geographical profiling​
• what does investigative psychology involve?

  1. interpersonal coherence
  2. significance of time and place
  3. criminal characteristics
  4. criminal career
  5. forensic awareness
• what is interpersonal coherence? - investigative psychology bottom up

  • behaviour - including interaction with victim which may reflect everyday behaviour
  • controlling eg
• investigative psychology bottom up - significance of time and place what is it?


  when the crime happened and where. indicate where offender lives
• investigative psychology- criminal characteristics what is it? BU

  placing criminals into categories
• investigative psychology what is criminal career? BU

  considers how far into their criminal career experience offenders are and how their pattern of crime might progress
• investigative psychology - forensic awareness - BU 


  knowledge of the cjs and potential previous subject of the police eg. covering tracks
• what is geographical profiling?

  bottom-up profiling first described by Rossmo (1997) ​

  • It is based on the principle of spatial consistency – that an offenders operational base and future offences are linked.​
  • Crime mapping is used to link local crime statistics, local transport and the geographical spread to make inferences about the likely home or operational base, workplace and social hangouts of the offender. ​
  • The assumption is that serial killers will restrict their ‘work’ to areas they are familiar with – WHY?​
• What is the circle theory?

  Circle theory: People operate within a limited spatial mind set that creates imagined boundaries in which crimes are likely to be committed.
• what is a marauder? Circle theory

  ​

  The Marauder: the offender operates in close proximity to their home base. 
• what is a commuter?

  The Commuters: the offender is likely to have travelled a distance away from their usual residence. 
•     what is the atavistic form?

  • This is a biological approach to offending that assumed that the innate physiological make-up (genes) of the person caused them to become a criminal. I.e. they are born to become criminals.​
  • Atavistic form saw offenders as ‘genetic throwbacks’ or ‘primitive sub-species’ who were biologically different from non-criminals.​
• the atavistic form suggests?

  • They lack evolutionary development – their savage and untamed nature meant that they would find it impossible to adjust to the demands of civilised society and would inevitably turn to crime. ​
  • They are distinguishable by particular facial features and cranial characteristics.
• lombroso argued that?

  • Lombroso argued that criminals could be identified by particular facial, cranial and bodily characteristics as well as other characteristics which are all biologically determined:​
  • Facial and cranial features – narrow, sloping brow, strong prominent jaw, high cheekbones and facial asymmetry.​
  • Bodily features – dark skin, extra toes, nipples or fingers.​
  • Other characteristics – insensitivity to pain, use of slang, tattoos and unemployment.​
• Lombroso even categorised particular types of criminal in terms of their physical and facial characteristics: ​

  • Murderers: bloodshot eyes, curly hair and long ears ​
  • Sexual deviants: Glinting eyes, Swollen, fleshy lips​
  • Fraudsters: Thin and reedy lips
• what did goring 1913 suggest about atavistic form?

  Goring (1913) compared 3000 criminals and 3000 non-criminals and concluded that there was no evidence that are offenders are a distinct group with unusual facial and cranial characteristics, but many criminals did tend to have lower intelligence.
• what is the biological explanation?

  The biological approach suggests that crime is an innate tendency which may be genetically determined or the result of abnormalities in brain structure or function. 
• what is the genetic explanation?

  • Genetic explanations suggest that offenders inherit a gene, or combination of genes, that predisposes them to commit crime. ‘Criminal’ genes are transmitted from parent to child. The activity of two particular genes (MAOA and CDH13) have been implicated in offending behaviour.​
• what is the neural explanation?

  • Neural explanations suggest that offenders commit crime because of dysfunctions of the brain and nervous system. This includes the activity of brain structures and neurotransmitters.
• lange 1930 suggests that?

  • Lange (1930) investigated 13 MZ twins and 17 DZ twins where one of the twins in each pair had served time in prison. Lange found that 10 of the MZ twins and 2 of the DZ twins had a co-twin who was also in prison.​
• Christiansen (1977) - biological approach

   studied 87 MZ and 147 DZ twins and found a concordance of 33% for MZ twins and 12% for DZ twins.
• what is the diathesis stress model?

  Offending behaviour is argued to be the result of both an underlying (genetic) predisposition (diathesis) and an environmental trigger (stress – e.g. being raised in a dysfunctional environment or having criminal role models). Both are necessary for offending behaviour to occur. 
• who was Stephen Mobely?

  as a convicted murderer executed by the State of Georgia for the 1991 killing of John C. Collins, a 25-year-old college student working nights as a Domino's pizza store manager. On appeal, Mobley's attorneys advanced a novel argument that Mobley was genetically predisposed to seeking violent solutions to conflict as four generations of his family had been responsible for a range of violent and criminal acts, including rape and murder.
• what did eysenck propose?

  •  proposed that offending behaviour is caused by having a criminal personality (psychological). ​
  • However, he argued that the criminal personality type is biological in origin (i.e. has an innate, biological basis) and comes about through the type of nervous system we inherit. ​
• eyesenck personality dimensions what are they?

  • high extraversion
  • high neuroticism
  • high psychoticism
• what did eysencks theory of criminal personality?

  • Eysenck suggested that the criminal personality type is the neurotic-extravert ​
  • i.e. they score highly on measures of neuroticism (unstable and overly anxious and nervous) and extraversion (sensation-seeking and outgoing). ​
  • Additionally, offenders will score highly on measures of psychoticism – cold and unfeeling and prone to aggression. ​
  • This is measured using the Eysenck Personality Inventory (EPI). A later scale was introduced to measure psychoticism.​
• eysencks theory of criminal personality - what are extraverts claimed to have?

   have a chronically under-aroused nervous system, meaning they constantly seek excitement, stimulation and are likely to engage in risk-taking and dangerous behaviours, which may explain some offending behaviour.
• Neurotics in a criminal personality have a more reactive?

  • sympathetic nervous system
  • hey are unstable and so react easily and get upset quickly. They may therefore overreact to situations of threat, explaining some offending behaviour