Forensics - bottom up approach

Question 1

aim of bottom up approach

Answer 1

generate picture of offender through systematic analysis of evidence at the crime scene

Question 2

what are the two main types of bottom up approach

Answer 2

investigative psychology and geographical profiling

Question 3

who is the key psychologist associated with investigative psychology

Answer 3

Canter

Question 4

why is it called the bottom up approach

Answer 4

profilers work up from evidence, don’t work down from fixed categories

Question 5

procedure of investigative psychology

Answer 5

• statistical analysis alongside theory
• establish patterns of behaviour
• details of offence can be matched to suggest details about offender
• build profile of offender
• determine if series of crimes are linked

Question 6

5 key assumptions of investigative psychology?

Answer 6

1. interpersonal coherence -> consistency in criminal behaviour + real life behaviour
2. time and place significance -> can indicate where offender lives/works
3. forensic awareness -> covering tracks well = previous experience in interrogation?
4. criminal career -> crimes changes due to experience
5. criminal characteristics -> typical characteristics typically found in particular crime

Question 7

procedure/assumptions of geographical profiling

Answer 7

criminals work in an area well known to them (schema theory/cognitive mapping) but there is a buffer zone around their house
make inference about offenders ‘base’ (crime mapping)
suggest if crime is opportunistic or planned

Question 8

jeopardy surface

Answer 8

criminals home

Question 9

Canter’s circle theory

Answer 9

crimes will usually form a circle around criminals base

Question 10

how did Canter help in the capture of The Railway Rapist?

Answer 10

used geographical information from crime scene to draw up a profile that was very accurate

Question 11

two types of criminals (geographic)

Answer 11

1. marauder - operates in close proximity to home
2. commuter - likely to travel distance away from usual residence

Question 12

strengths of the bottom up approach

Answer 12

+ evidence supporting approach. Canter analysed 66 SA cases, several behaviours identified as common. each individual showed patterns of behaviour = consistent
+ evidence supporting geographical profiling. Lundrigan and Canter analysed 120 murder cases. found spatial consistency and circular effect around base

Question 13

limitations of the bottom up approach

Answer 13

• geographical profiling not sufficient on its own. success relies on accuracy of data from police. 75% of crimes not even reported. other factors need to be looked at when creating profile.
• offender profiling has led to mixed results. Copson studied 48 police depts. profiling only lead to identifying real offender 3%.
• Rachel Nickell case -> profile led to arrest of wrong person
• Kocis found chemistry students made more accurate profiles than senior detectives