Offender profiling: bottom-up approach

Question 1

What is the bottom-up Approach?

Answer 1

It was created by David Canter (1990) and revolves around data analysis and geographical profiling, investigative psychology, and building a profile of an offender based on facts rather than hunches.

In bottom-up profiling, investigators refrain from making any assumptions until crime scene data has been scrutinised, and comparisons have been made to similar crimes where data has already been recorded.

The aim of this approach is to build a picture of the offender, their likely characteristics, routine behaviour and social background through systematic analysis of evidence at the crime scene.

Question 2

What is Investigative Psychology?

Answer 2

The discipline of investigative psychology is an attempt to apply statistical procedures (alongside psychological theory) to the analysis of the crime scene.

Question 3

What are the 5 assumptions that underpin investigative psychology?

Answer 3

1)Interpersonal coherence
2)Time and place
3)Criminal characteristics
4)Criminal career
5)Forensic awareness

Question 4

What is Interpersonal coherence assumption?

Answer 4

We assume behaviour is consistent across situations e.g. everyday behaviour is similar to way we behave at a crime scene e.g. aggressive person is going to commit an aggressive crime.

Question 5

What is Time and place assumption?

Answer 5

Time and location give clues as to where the offender may live or work.

Question 6

What are Criminal characteristics assumptions

Answer 6

Placing criminals into categories is a useful exercise to help the police.

Question 7

What are Criminal career assumptions?

Answer 7

This considers how far into their criminal experience offenders are and how their pattern might progress.

Question 8

What are Forensic awareness assumptions?

Answer 8

Offenders who show an awareness of forensic investigation e.g. by cleaning a crime scene will probably have committed a crime before and been through the criminal justice system (CJS).

Question 9

What is Geographical Profiling?

Answer 9

Geographical profiling is a later addition to bottom-up profiling, created by David Canter (2008), that refers to the analysis of crime locations and times, to identify patterns of an offender.

Involves a comprehensive analysis of the location of crimes. Profilers are able to establish whether an offender is a commuter (appears to travel to commit crimes) or a marauder (appears to stay local, possibly near a workplace or home).

The analysis of locations also allows profilers to establish a jeopardy circle – an area that is likely to contain the next crime, based on emerging patterns.

Question 10

Similarities between the top-down approach and the bottom-up approach

Answer 10

Both are used to narrow the field of suspects.
They both assume that there is a pattern in an offender’s behaviour, which is not always the case.

Both have captured the public’s imagination.

Question 11

Differences between the top-down approach and the bottom-up approach

Answer 11

Top-down Originates in law enforcement expertise where as Bottom-up Originated in psychological expertise.

Top-down Is based on qualitative methods and creating hypotheses from scrutiny of the crime scene and witness reports whereas Bottom-up Is based on quantitative statistical analysis.

Top-down Is used mainly for murder and rape whereas Bottom-up Can be used for all types of crime.

Top-down focuses on evidence found at the crime scene which is then used to infer. where as Bottom-up Focuses on distribution of crimes in the area.

Top-down work down to assign offenders into categories whereas Bottom-up Work up from evidence collected at the crime scene.

Question 12

Strength of bottom up approach with regards to successful applications.

Answer 12

P: One strength of the bottom-up approach is that it has been used successfully to catch offenders.
E: Canter used his approach to provide an offender profile for the ‘railway rapist’ (John Duffy) who had sexually assaulted and murdered women near railway stations in London.
C: This confirms that the bottom-up approach to offender profiling does have useful applications in fighting crime.

Question 13

Strength of bottom up approach with regards to Usefulness for day to day crime

Answer 13

P: The bottom-up approach is praised for its usefulness in a wider range or criminal behaviours than top-down offender profiling.
E: Whilst top-down approaches are limited to extreme offender behaviours such as rape and murder, bottom-up approaches are successfully used in more day-to-day crimes such as theft and vandalism.
C: Therefore, there is more opportunity for bottom-up profiling techniques to be applied, making this a more suitable method for offender profiling.

Question 14

Strength of bottom up approach with regards empirical evidence

Answer 14

P: One strength of the bottom-up approach is that it is deemed to be highly scientific as the foundation of its approach is based on data.
E: Decisions are data-driven, the approach is objective and refrains from forming profiles with hunches and subjective interpretations from crime scenes.
C: This contrasts with the top-down approach to offender profiling, which is not reliant on data and instead is built with a hypothesis about offender behaviour based on the templates derived from subjective interviews of extreme offenders.

Question 15

Weakness of both top-down and bottom-up approaches with regards to I&D.

Answer 15

P: The two methods of offender profiling could be criticised for being socially sensitive and a hindrance to police investigations.
E: Many argue that there is a danger that too much emphasis may be put into building offender profiles at the sacrifice of using other police resources that may prove to be crucial in an investigation. In addition, there could be instances where profiles have been inaccurate and led to miscarriages of justice.
C: Although there are benefits to offender profiling, many would argue that it should be overly relied upon – it should complement an investigation, rather than lead it.