bottom up approach

Question 1

who developed the bottom up approach

Answer 1

Canter

Question 2

what did canter propose regarding offender profiling

Answer 2

• proposed profiling can and should be based on psychological theory + research

Question 3

define the bottom up approach

Answer 3

data driven approach where statistical technqiues are used to produce predictions about likely characteristics of offender

Question 4

what are the 3 main features of the bottom up approach

Answer 4

• interpersonal coherence
• forensic awareness
• small space analysis

Question 5

outline what interpersonal coherence is as feature of bottom up approach

Answer 5

• people tend to be consistent in their behaviour - how they behave at scene is how they may behave elsewhere

Question 6

outline forensic awareness as a feature of bottom up approach

Answer 6

• certain behaviours reveal awareness of particular police techniques + from past experiences
• individuals arrested before found to conceal more due to previous knowledge of criminal system

Question 7

outline small space analysis as feature of bottom up approach

Answer 7

• data from crime scenes + offender characteristics are correlated so most common connections can be identified
• trying to predict future data

Question 8

who developed small space analysis

Answer 8

Canter

Question 9

supporting evidence for small space analysis being main feature of bottom up approach

Answer 9

• salfati + canter analysed co occurrence of 48 crime scenes + offender characteristics which were taken from 82 murder cases were victim was stranger
• they found 3 themes

Question 10

what were the 3 themes identified when Salfati and Canter analysed co occurance of crime scenes

Answer 10

• instrumental opportunistic (instrumental - accomplishing a goal, opportunistic - offender took easiest opportunities)
• instrumental cognitive (concern abt being detected - more planning)
  expressive impulsive (uncontrolled offence - heat of moment, may feel provoked by victim)

Question 11

define geographical profiling

Answer 11

analyses location of series of crime scenes and considers how they may relate to offenders place of residence

Question 12

how did Canter help towards geographical profiling

Answer 12

he proposed people do not just reveal themselves through the crimes they commit but through locations they choose
- location of crime can be clue in investigation

Question 13

who proposed circle theory

Answer 13

canter and larkin

Question 14

outline circle theory

Answer 14

Canter and Larkin proposed most offenders have spatial mindset when committing crime (commit them in imagined circle)
- criminals base would be in centre of circle
- identified two forms of offenders (marauders and commuters)

Question 15

what is a marauder - circle theory

Answer 15

offender commits crime within same geographical areas their residence

Question 16

what is a commuter - circle theory

Answer 16

offender travels to another geographical area and commits crime within defined space

Question 17

who developed criminal geographical targeting

Answer 17

rossmo

Question 18

define what criminal geographical targeting is

Answer 18

• computerised system based on Rossmo’s formula which produces 3 dimensional maps (Jeopardy surface)

Question 19

what is a jeopardy surface (what do the colours on it indicate)

Answer 19

map used in criminal geographical targeting - different colours indicate likely closeness of residence

Question 20

what does a Jeopardy surface display

Answer 20

displays data relating to time, distance and movement of offender too and from crime scene

Question 21

evaluation points for bottom up approach to offender profiling

Answer 21

scientific basis BUT biased (-)
usefulness (+)
circle theory lack of success (-)
dangers of profiling (-)

Question 22

expand on eval point - scientific basis BUT biased (-)

Answer 22

• bottom up approach considered to be more scientific than top down approach due to use of objective statistical techniques and computer analysis
• BUT issues occured with approach - data used to drive system is only related to offenders who have been caught (tell little about patterns of behaviour related to unsolved crimes)
• using computer programmes - someone has to develop formula used and may be incorrect (vulnerable to human error)
• means bottom up approach has potential to be objective and systematic however when used it can be biassed.

Question 23

expand on eval point - usefulness (+)

Answer 23

• Canter’s first attempt at profiling led to police interested in method used
  research supports usefulness
• Copson surveyed 48 police forces, found 75% of police officers said profiler advice was useful and would use profiler again
• suggested method may not be useful in identifying actual offender but benefits outweigh
• profiling been proven useful for some

Question 24

expand on eval point - circle theory lack of success (-)

Answer 24

• Canter and Larkin studied 45 sexual assaults, showed support for model by distinguishing whether they were marauders or commuters
• 91% offenders were marauders - classification doesnt seem useful as almost all offenders are marauders
• Petherick pointed out number of flaws in model : if persons home base is not actually centre of circle it means police may lookin in wrong place
• limiting approach and its effectiveness because there are critics going against theory (lacks validity)

Question 25

expand on eval point - dangers of profiling (-)

Answer 25

• although profiling is useful in helping police narrow down field of possibilities - sticking to closely with one profiler can cause mistakes down to human error
• example : case of Nickell who was stabbed in Wimbledon, forensic psychologist Paul Britton helped police to create profile which led to identification of Colin Stagg which later turned out actual murderer was Robert Napper who had been ruled out due to his height not matching picture
• using bottom up approach is can limit findings due to decisions being made too soon all down to human error
• limiting the validity