Forensics L1-2 Flashcards
1
Q
What is offender profiling?
A
- tool used by the police to narrow down the list of likely suspects for a crime or crimes
- based on the idea that characteristics of offender can be deduced from details of offence and crime scene
2
Q
What do profiling methods usually involve?
A
- can vary but usually involve common things
- careful scrutiny of crime scene
- analysis of evidence, including witness reports
- allows generation of hypothesis about probable characteristics of the offender
- like age, background and occupation
3
Q
What is the top down approach to profiling?
A
- templates of organised offender and disorganised offender are pre-existing in mind of profiler
- evidence from crime scene and other details of crime/victim/context then used
- fit the offender into either of the two pre-existing categories
4
Q
What is meant by organised offenders, TD?
A
- show evidence of having planned the crime in advance
- victim is deliberately targeted as killer or rapist has preference for a certain victim
- offender maintains high level of control during crime
- little evidence left behind at crime scene
- offenders tend to be of above average intelligence
- in a skilled, professional occupation
- and socially and sexually competent
- often married with children
5
Q
What is meant by disorganised offenders, TD?
A
- offenders show little evidence of planning
- suggesting offence maybe spontaneous
- crime scene tends to reflect impulsive nature of attack
- body usually left at scene and appears to have been very little control on part of the offender
- offender tends to be of lower than average intelligence
- in unskilled work or unemployed
- often have history of sexual dysfunction or failed relationships
- tend to live alone and often relatively close to where the offence took place
6
Q
Top down profiling, -ve (has no+ve)?
A
- only applies to certain crimes like rape and murder
- does not work well with common offences like theft
- as crime scene reveals very little about the offender
= organised or disorganised distinction developed based on interviews with 36 serial killers in the USA
= critics pointed out that this is too small + unrepresentative a sample to base a typology system on - developed based on interviews with 36 sexually motivated serial killers, including Ted Bundy and Charles Manson
- Canter (2004) argued not valid to rely on self-report data from convicted serial killers when constructing a classification system
= organised or disorganised distinction overly simplistic
= Holmes (1989) suggests four types of serial killer; visionary serial killer (kill because God/devil telling them), mission serial killer (to eradicate a group of people seen as undesirable), hedonistic serial killer (for the thrill) and power serial killer (to have control over victims) - Canter et al. (2004) analysed data from 100 murders in USA with reference to the supposed typical characteristics of organised and disorganised killers
- findings did suggest evidence of a distinct organised type
- but not the case for disorganised type which undermines the entire classification system
7
Q
What is the bottom up approach to profiling?
A
- developed in the UK
- aim is to generate a picture of offender
- including likely characteristics, routine behaviour, and social background
- achieved through systematic analysis of evidence left at the crime scene
8
Q
How does the bottom up differ from the top down approach?
A
- bottom up does not begin with fixed typologies like top down
- instead profile is data-driven and emerges as the profiler engages in rigorous scrutiny of the details of the offence
- bottom-up profiling far more grounded in psychological theory than the top-down approach
9
Q
What is the aim of investigative psychology, BU?
A
- to establish a statistical database of behaviours which occur at crime scene and characteristics of offenders who carry out these behaviours
- specific details of offence can then be matched against this database to reveal statistically probable details about the offender
- like their personal history, family background etc
- can also help determine whether multiple offences are linked and likely to have been committed by same individual
10
Q
What is interpersonal coherence, IP BU?
A
- central to investigative psychology is concept of interpersonal coherence
- suggests the way the offender behaves at the crime scene is similar to how they behave in their everyday life
- e.g. whilst some rapists want to control and humiliate their victim, others can be apologetic
- might tell the police how the offender relates to women more generally
11
Q
What is the significance of time and place, IP BU?
A
- key variable
- details of time crime occurred and place it occurred in
- may indicate where the offender is based
- like where they live and work
- or their mode of travel
- like train or car
12
Q
What is forensic awareness, IP BU?
A
- describes individuals who have made an attempt to ‘cover their tracks’
- behaviour may indicate they have been the subject of police interrogation in the past
- or even that the police already have their DNA or fingerprints on file
13
Q
What is geographical profiling, BU?
A
- study of spatial behaviour in relation to crime and offenders
- focuses on location of crime as clue to where offender lives, works and socialises
- relevant data includes the crime scene, local crime statistics, local transport, and geographical spread of similar crimes
- assumption is that a serious offender will restrict their criminal activities to familiar area
- so offender’s base will be in the middle of spatial pattern of crime scenes
- earlier crimes likely to be closer to offender’s base than later crimes
- as offender becomes more confidence they will often travel further from their comfort zone
14
Q
What are the 2 models of offender behaviour, GP BU?
A
- Canter + Larkin (1993) propose two models of offender behaviour
1. the marauder, who operates close to their home
2. the commuter, who is likely to have travelled a distance away from their home - spatial pattern of their crime scenes will still form a circle around their home
- this becomes more apparent the more offences that are committed
15
Q
What things can the spatial pattern of a crime tell the police, GP BU?
A
- whereabouts of offenders base
- whether the crime was planned or opportunistic
- mode of transport
- employment status
- approximate age
16
Q
Bottom up profiling, +ve?
A
- Canter argues bottom-up more scientific than top-down
- as it is more grounded in evidence and psychological theory
- and less driven by speculation and hunches than top-down
= can be applied to a wide variety of offences like theft as well as murder and rape unlike top down
17
Q
Bottom up profiling, -ve?
A
- have been some significant failures when using bottom-up profiling
- in 1992, 21 year old Rachel Nickell stabbed 47 times and sexually assaulted in frenzied attack on Wimbledon Common
- in 2008, following examination of forensic evidence, Robert Napper was convicted of the murder
- he had been ruled out early on in the initial investigation because several inches taller than profile had claimed the offender would be
= Copson (1995) surveyed 48 police forces
= found that the advice provided by a profiler was judged to be useful in 83% of cases
= but in only 3% of cases did it lead to the accurate identification of the offender - Kocsis et al. (2002) found chemistry students produced more accurate offender profile than experienced senior detectives
- implies that the bottom-up approach is little more than common sense and guess work
