5.3 The Bottom Up Approach

Question 1

define the bottom-up approach

Answer 1

a data-driven approach where statistical techniques are used to produce predictions about the likely characteristics of an offender

Question 2

define geographical profiling

Answer 2

a form of bottom-up profiling based on the pattern shown by the location or locations of a series of crimes

Question 3

define investigative psychology

Answer 3

a form of bottom-up profiling based on psychological theory

Question 4

who created the bottom-up approach in investigative psychology. Why was it created at the time and what was it known as?

Answer 4

It was developed by David Canter, who was hired to catch the Railway Rapist
Canter’s model is known as the Five Factor Model

Question 5

list the 5 features of David Canter’s five factor model

Answer 5

interpersonal coherence
time and place
criminal characteristics 
criminal career
forensic awareness

Question 6

describe ‘Interpersonal coherence’, as used in Canter’s five factor model

Answer 6

there is a consistency between the way offenders interact with their victims and with others in their everyday lives.

Question 7

describe ‘time and place’, as used in Canter’s five factor model

Answer 7

the time and location of an offender’s crime will communicate something about their own place of residence/employment.

Question 8

describe ‘criminal characteristics’, as used in Canter’s five factor model

Answer 8

characteristics about the offender can help to classify them, which helps the police investigation.

Question 9

describe ‘criminal career’, as used in Canter’s five factor model

Answer 9

crimes tend to be committed in similar fashion by offenders and can provide indication of how their criminal activity will develop.

Question 10

describe ‘forensic awareness’, as used in Canter’s five factor model

Answer 10

offenders who show an understanding of a police investigation are likely to have had previous encounters with the criminal justice system.

Question 11

summarise the bottom-up approach in offender profiling

Answer 11

data driven and based on psychological theory and research
investigative psychology - using characteristics of the person (Canter).
- interpersonal coherence, personality is consistent which provides clues, and changes in circumstance may provide other clues
- forensic awareness, an experienced criminal may reveal their knowledge, e.g. wiping fingerprints
- smallest space analysis, data items from crime scenes correlated, leading to three themes: instrumental opportunistic, instrumental cognitive and expressive impulsive
Geographical profiling, location of a crime provides clues (Canter)
- circle theory (Canter and Larkin), criminals commit crimes within a circle: marauder (live within the circle) or commuter (travels to the circle)
- criminal geographic targeting (CGT), Rossomo’s formula produces a 3D map (jeopardy surface) which will show probability of offender residence

Question 12

evaluate the bottom-up approach in offender profiling

Answer 12

scientific basis - computer programs based on incomplete data (related to solved rather than unsolved crimes) and algorithms may be incorrect
Is investigative psychology useful? Copson found 75% of police thought profiler’s advice was useful but not used that much in the UK
is circle theory successful? Canter and Larkin found support but very few ‘commuters’; the concept assumes an offender lives in the centre of a shape that is circular
is geographical profiling successful? can help prioritise house-to-house searches but not much better than traditional pins on map
final conclusions - can’t identify murderer but can narrow field, but has potential to be misleading as in case of Rachel Nickell

Question 13

who developed smallest space analysis?

Answer 13

David Canter

Question 14

what is smallest space analysis?

Answer 14

statistical technique
data about many crime scenes and offender characteristics are correlated so the most common connections can be identified

Question 15

when looking at smallest space analysis, what does it mean for an offender to be ‘instrumental opportunistic’

Answer 15

‘instrumental’ refers to using murder to obtain something or accomplish a goal; ‘opportunistic’ means that the offender took the easiest opportunities

Question 16

when looking at smallest space analysis, what does it mean for an offender to be ‘instrumental cognitive’

Answer 16

‘instrumental’ refers to using murder to obtain something or accomplish a goal; ‘cognitive’ means the offender has a particular concern about being detected and therefore more planned

Question 17

when looking at smallest space analysis, what does it mean for an offender to be ‘expressive impulsive’

Answer 17

uncontrolled, in the heat of strong emotions, may feel provoked by victim

Question 18

how does geographical profiling work?

Answer 18

analyses the locations of a connected series of crimes and considers where the crimes were committed, the spatial relationships between different crime scenes and how they might relate to an offender’s place of residence

Question 19

who proposed the use of geographical profiling? what was their reasoning behind its use?

Answer 19

David Canter
people do not just reveal themselves through the crimes they commit but also through the locations they chose
geographical profilers are concerned with where rather than who.
It makes sense to assume that offender are more likely to commit a crime near where they live or where they habitually travel to because it involves least effort, thus making the location of a crime a potential prime clue in an investigation

Question 20

when looking a geographical profiling, circle theory can be used. Who proposed it, why?

Answer 20

David Canter and Paul Larkin, 1993

proposed that most offenders have a spatial mindset - they commit their crimes with a kind of imagined circle

Question 21

when looking a circle theory in geographical profiling, two types of offenders were proposed, can you describe the,?

Answer 21

marauder - the offenders home is within the geographical area in which crimes are committed
commuter - the offender travels to another geographical area and commits crimes within a defined space around which a circle can be drawn

Question 22

what is criminal geographic targeting

Answer 22

a computerised system developed by Kim Rossmo and based on Rossmo’s formula
the formula produces a three dimensional map displaying spatial data related to time, distance and movement to and from crime scenes
the map is called a jeopardy surface, colours are used to indicate likely closeness to a crime scene