Forensic Psychology

Forensic Psychology

1. Defining and measuring crime

   • Official statistics
     • stats based on any incident reported to the police
     • AO3: only a certain number of crimes get reported to the police - dark figure
   • Victim surveys
     • asking a sample to identify which crimes have been committed against them over a fixed period of time
     • AO3: provides info about the dark figure of crime - but depends on honesty.
     • A03: 75% take part = biased sample
   • Offender surveys
     • increase knowledge about criminal behaviour by questioning offenders
     • AO3: problems with honesty, however, the OCIS report that p's said they were honest

2. Offender profiling: top-down approach

   • crime scene analysis - judgements by profiler - data
   • 6 stages of the top-dwn process
     • stage 1: profiling inputs - background info about victim, crime details and description
     • Stage 2: decision process models - organise data into meaningful patterns
     • Stage 3: crime assessment - organised vs disorganised offenders
     • Stage 4: criminal profile - profile constructed to work out strategies to help catch them
     • Stage 5: crime assessment - persons matching the profile re evaluated. If no evidence = back to stage 2
     • Stage 6: apprehension - when suspect is apprehended, the entire process is reviewed to check conclusions made were legitimate
   • AO3
     • police who have used the top-down approach believe it is useful (82%)
     • method is flawed - based on extreme cases which aren't representative of the population
     • may cause harm due to wrong convictions as it is based on judgements of the profiler

3. Offender profiling: bottom-up approach

   • Investigative psychology
     • Interpersonal coherence - looking out for correlations in people's behaviour
     • forensic awareness - certain behaviours deduced from crime scene analysis may reveal awareness of police techniques - aid profiling
     • smallest space analysis - data about crime scene and offender are analysed to produce underlying theme
   • geographical profiling
     • analyses relationship between crime scenes and how they might reveal the offenders place of residence
     • circle theory - offenders commit crime in an imagined circle. Marauder and commuter
   • AO3
     • more scientific than top-down - uses objective statistical techniques
     • research supports usefulness - 75% of police said it was useful, however, only 3% said it helped identify the offender
     • geographical profiling can be useful in prioritising house to house searches
     • suggests that profiling can't identify an offender. All it does is narrow down the field of possibilities

4. Biological explanations of offending behaviour: a historical approach

   • atavistic form
     • certain people are born with a criminal personality - this innate personality is a throwback to primate forms
     • Lombroso - criminals are genetic throwbacks with atavistic features such as high cheekbones, strong jawline, etc.
   • empirical evidence
     • Lombroso based his theory on post-mortem exams of criminals and studying faces of living criminals
     • study - he found that 21% had just one atavistic trait and 43% had atleast 5
   • environmental influences
     • Lombroso realised that a persons physical and social environment need t be considered
     • 3 types of criminals: born, insane and criminaloids
   • Somatotypes
     • criminals fall into 4 somatotypes: leptosome, athletic, pyknic and dysplastic
   • AO3
     • androcentrism
     • support for link between body type and criminality
     • lack of controls - he didn't pay the same attention to non-prisoners - he may have found the same characteristics in non-prisoners

5. Biological explanations for offending behaviour: genetic and neural

   • genetic explanations
     • twin studies - found 52% CR for MZ twins and 21% for DZ twins
     • abnormalities in MAOA and CDH13 = responsible for criminal behaviour
     • study of 900 offenders found low MAOA and CDH13 activity - concluded 5-10% of all violent crimes were due to abnormalities in one of them
     • AO3
       • research support from adoption studies - adopted children with criminal bio. parent = 50% greater risk of having a criminal record
       • deterministic - not everyone with the same genes becomes a criminal
   • neural explanations
     • offenders have reduced functioning in the prefrontal cortex - involved in regulating emotion and controlling moral behaviour
     • abnormalities in the limbic system of murderers
     • low levels of serotonin = aggression and criminal behaviour because serotonin inhibits the prefrontal cortex
     • very high and very low levels of noradrenaline = aggression and criminality
     • AO3
       • research has led to treatment - e.g people in prison could be given a diet that would enhance serotonin
       • research relies on studies of non-human animals = not studying criminality but aggressiveness
       • deterministic