Lesson 2 - Bottom Up Approach to Offender Profiling

Question 1

What is the Bottom-Up approach?

Answer 1

The bottom-up approach is where profilers systematically analyse evidence left at the crime scene in order to generate a picture of the offender, including their characteristics, behaviour and social background.

Question 2

How is the bottom-up approach different from the top-down approach?

Answer 2

The bottom-up approach does not begin with fixed typologies / classification systems but is instead data-driven and emerges as a result of detailed scrutiny of the crime scene. The bottom-up approach is much more grounded in psychological theory that the top-down approach.

Question 3

What is investigative psychology?

Answer 3

Investigative psychology is where behaviours are established that are likely to occur at certain crime scenes. These behaviours are turned into a statistical database which acts as a baseline to compare similar crimes to. For example, a crime can be matched to the database in order to reveal statistically probable details about the offender and can also help determine whether lots of crimes may all be linked to the same offender.

Question 4

What are 3 concepts related to investigative psychology?

Answer 4

Interpersonal coherence
Significance of time and place
Forensic awareness

Question 5

What is interpersonal coherence?

Answer 5

Interpersonal coherence refers to the idea that the way in which an offender behaves at a crime scene, including how they interact with the victim, reveals their behaviour in everyday situations.

Question 6

What is an example of interpersonal coherence?

Answer 6

Some rapists want to control and humiliate their victims, as others are more apologetic. This may reveal how the offender relates to women in an everyday setting.

Question 7

What is significance of time and place?

Answer 7

This refers to how the time and place of the crime may indicate where the offender lives.

Question 8

What is forensic awareness?

Answer 8

Forensic awareness refers to the idea that offenders who attempt to ‘cover their tracks’ by hiding the boy or murder weapon, have likely been a subject of police interrogation in the past or have their DNA or fingerprints already on file with the police.

Question 9

What is geographical profiling?

Answer 9

Geographical profiling is the study of spatial patterns/spatial behaviour in relation to crime and offenders.

Question 10

What three things does the location of the crime potentially tell profilers about the offender?

Answer 10

Where they live
Where they work
Where they socialise

Question 11

What do profilers use when geographically profiling? (4)

Answer 11

The location of the crime scene
Local transport linked to the crime scene
Local crime statistics
The geographical spread of similar crimes which may be linked to others

Question 12

What is the assumption about geographical profiling with serious offenders?

Answer 12

The assumption is that serious offenders will restrict their criminal activities to an area they are familiar with where their home will often be in the middle of the spatial pattern of the crime scenes (the crime scenes often form a circle around the area in which they live).

Question 13

Are earlier or later crimes likely to be closer to the offenders base?

Answer 13

Earlier crimes are more likely to be closer to the offenders base where as the offenders’ confidence grows, they will often travel further from their area of comfort.

Question 14

What model did Canter and Larkin (1993) propose?

Answer 14

Canter and Larkin (1993) proposed two models of offender behaviour: marauder (who commits crimes close to their home) and the commuter (who travels a distance away from their home to commit their crimes). However, they realised that the spatial pattern of the crime scenes still formed a circle around their home.

Question 15

What other factors can the spatial pattern of a crime tell profilers about the offender? (4)

Answer 15

Whether the crime was planned or opportunistic 
Mode of transport 
Employment status 
Approximate age 
Etc;

Question 16

What are 2 strengths of the Bottom-up approach?

Answer 16

+ Canter argues that the bottom-up approach to offender profiling is more grounded in evidence and psychological theory than the top-down approach and is therefore more scientific.

+ Unlike top-down profiling, the bottom-up approach can be applied to a variety of offences, not just crimes such as murder, rape or arson, but things like burglary too.

Question 17

What are 3 weaknesses of the Bottom-up approach ?

Answer 17

• There have been significant failures while using the bottom-up approach. In 1992, 21 year old Rachel Nickell was stabbed 47 times and sexually assaulted in Wimbledon Common but the offender, Robert Napper, was not convicted of the murder until 2008 because he had been ruled out early on in the investigation simply because he was several inches taller than the profiler thought the offender was.
• Copson (1995) surveyed 48 police forces and found out that bottom-up profiling was useful for 83% of cases but only lead to the accurate identification of the offender 3% of the time - not very useful then.
• Kocsis et al. (2002) found that chemistry students could produce more accurate offender profiles that experienced senior detectives proving that the bottom up approach is little more than common sense and guess work.