forensic psychology Flashcards
what is profiling
the idea you can make assumption aboyt characteristics of an offender by analysing the offence they commit
what are the two approaches to profiling
top down- starts with theories about the type of offender–> theories applied to crime scene
bottom up- starts with evidence from the crime scene –> scientific and statistical predictions based on the evidence from this crime scene and other crimes
top down approach
- developed by FBI - USA
- starts with theories, typologies, crime scene = general to specific
- They then work downwards to assign an offender to one of the typologies
- Data is then entered into the data-base
- compared continually against other entries on the basis of certain aspects of the crime
- The purpose is to detect signature aspects of the crime and similar patterns
of ‘modus operandi’ (way of working)
Assumptions
Disorganised or organised crime scene
top down approach 4 stages
data assimilation
- investigators gather together info from multiple sources
crime scene classification
- profilers decide whether the crime scene represents an organised or disorganised offender
crime reconstruction
- hypotheses are generated about what happened during the crime
profile generation
- profilers construct a sketch of the offender including demographic and physical characteristics, behavioural habits
characteristics of organised crime
of offence:
- planned
- shows self control
- lack of evidence left at the scene
- targeted victim and tries to control the victim
- weapon hidden
of offender:
- above avergae IQ
- socially and sexually competent
- married/cohabiting
- anger or depression at the time of offence
- skilled occupation
post offence behaviour:
- returns to the crime scene
- volunteers information
characteristics of disorganised crime
of offence:
- unplanned/spontaneous
- likely to leave evidence at the scene
- victim randomly selected
- minimum use of constraint
- disorganised behaviour
of offender:
- lives alone, near the crime scene
- socially and sexually inadequate
- physically or sexually abused in childhood
- frightened or confused at the time of offence
- low intelligence/ no occupation
post offence behaviour
- return to the crime scene to relive the offence
- keep diary
- keep news articles of the incident
research for top down approach
fbi interviews initially carried out structured interviews with 36 serial sex murderers
- what led to offending
- what early warning signs were there
- what encouraged or inhibited offences etc
from interview responses, plus a thorough analysis of the details of their crimes by behvaioural science unit, they catagorised offenders of serious crimes (murder and rape) into organised and disorganised offenders
advanatages of top down research
- police officers interviewed: 82% it was useful, 90% would use again
- adopted by law enforcement agencies all over the world who have adapted and enhanced
- ## important in challenging the stereotypes that investigators may hold about offender which may mislead investigations
limitations of the top down approach
- assumes offenders are one thing or the other and that this is stable over time
- wilson et al suggest no assumption is correct, most offenders show both disorganised and organised characteristics
- ## different profilers may reach different conclusions
bottom up approach
- specific to general= starts with scientific evidence
- investigate psychology
- Geographical profiling
- assumes offenders leave a psychological fingerprint of unique behaviour
Assumptions
Interpersonal coherence = consistency between the way offenders interact with their victims and others in everyday lives
Time and place of crime will communicate something about the crime
what is geographical profiling
- looks at patterns in location and timing of offences to make judgements about links between crimes
- people reveal themselves in the location they chose as much as their behaviour
- ## offender more likley to commit a crime near to where they live
what is a marauder
- commits crime within a confined area
- bounded by psychological barriers
- operates within his/her awareness space
- ## likely to have an anchor point from which to operate
what is a commuter
- commits crime over large areas
- crosses cultural and psychological boundaries
- involves complex hunting strategies
- hunting area lack of anchor point
- harder to geographically profile
what is investigative psychology
- uses established psychological theories and methods of analysis to prodict offender characteristics from offending behaviour
- each crime recorded on to database
- statistical analysis detects patterns of behaviour
- details of each new crime are matched with this database in order to develop hypothesis about the likely characteristics of offender
- poeple are consistent in their behaviour and therefore will be links
bottom up research- copson
copson 1975
- surveyed 48 uk police forces
- 75% said profiles advice had been useful
- only 3% said it actually helped to catch the correct offender
- profiling was only used in 75 cases
- profiles useful for narrowing down suspects
bottom up approach advantages
- useful for narrowing down suspects
- more hollistic than top down approach
- increased validity
- statistical basis makes this more reliable
- can be applied to a wide range of offences
bottom up approach limitations
- too generic and may not apply to too many people
- simplifying an imagined circle is also problematic and may not be as scientifc as suggested
What is smallest space analysis
Developed by canter
Data about many crime scenes and offender characteristics are correlated so
that the most common connections can be identified
Central to this approach is Interpersonal Coherence - behaviour of the offender
at the time of the crime will be comparable to what they are like everyday
What is the atavistic form explanation
Lombroso
Based on biological factors
Suggests some people born with criminal personality= innate
Criminals can be identified by the way they look
Lombroso 1876
Identify distinguishing physical features among male criminals which set them apart as offenders
- examined features and measurements of nearly 4000 criminals and skulls of 400 dead criminals
- 40% of those examined had atavistic features
What are atavistic features
General markers
Narrowing, sloping brow
Prominent jaw
High cheekbones
Facial asymmetry
Curly hair
Long eats
Atavistic characteristics for female offenders
Shorter
More wrinkled
Darker hair
Smaller skulls
Kurtzberg 1986
Found prisoners behaviour had improved following facial surgery
Those who had surgery-tendency to reoffend=42%
those who didn’t surgery-tendancy reoffend= 70%
Those who had facial surgery tended to do better on release from prison than those who did not
What are somatotypes
Certain atavistic features associated with certain crimes
Kretschmer 1921
tall and thin - petty thieves
tall and muscular - crimes of violence
Short and fat - crimes of deception and sometimes violence
More than one type- crimes against morality
Advantages or atavistic
Lombroso was first person to bring science and bio of person to study of crime
Led to investigation of further biological explanations such as genes & structure of brain
Limitations of atavistic
Racist as individual who has those features does not make them a criminal e,g, African Americans have curly hair, does not make them criminals
Unscientific approach
Correlation does not mean causation
Didn’t pay attention to criminals outside of prison
- goring 1913- compared 3000 convicts with 3000 non convicts and found no significant difference
- deterministic
genetic explanation
having particular gene or gene variant could influence someones offending behaviour
MAOA gene
what is the MAOA gene and what does it do
produces MAOA enzyme which breaks down groups of neurtransmitters in the synapse
what is MAOA L
low
- producing less of MAOA enzyme
- impacts neurotransmitters- serotonin
- this impacts part of the brain - amygdala, prefrontal corte
han brunner dutch family
large dutch family, 25 males
all had MAOA gene- all involved in impulsively aggressive violent criminal behaviour
5 significantly more violent than others as they had MAOA (L)
when gene is not functioning correctly - individuals display aggressive behaviour
1995- animal studies
- genetically engineered mice with MAOA (L)
- mice had abnoraml serotnonin levels
- older mice- more aggressive
- mice not humans
- no conscious thoughts
- cant be generalised to humans
- layer of additional support add to what already known
twin studies- christianson
- 3586 twin pairs
- denmark
- male concordance rate for identical twins being criminals was more than double than non identical
- however not even 50%
- suggests other influences on peoples offending behaviour
- similar with females but less as males seen to be more aggressive due to x chromosone coming just from mum so is stronger
genes themselves are not a whole explanation for criminal behaviour - low concordance rtes
higher concordance in identical than non identical suggesting there is heritability to criminal beahviour
twins reared apart tudy- grove
try to eliminate impact of nurture
- grown up in different environments
- 32 MZ twin pairs
- assessed through tests and interviews
- alcohol drug problems, antisocial beahviour in child and adulthood
- positive correlation between genetic influences and symptoms of childhood antisocial behaviour and adulthood
- antisocial behaviour increased with age
- environment can modify effects of genetics
neural explanation
brain structures, neurotransmitters
