Forensic psychology - The bottom-up approach

Question 1

What is the bottom-up approach?

Answer 1

• The bottom-up approach is an evidence based approach that uses statistical analysis of data collected at the crime scene and information such as choice of victim and location
• Also referred to as investigative psychology, the approach was developed by David Canter

Question 2

What is the five factor model?

Answer 2

• Interpersonal coherence (Interactions are the same in personal life)
• Time and place significance
• Criminal characteristics
• Criminal career (Changes with experience)
• Forensic awareness (Knowledge of police techniques)

Question 3

What is geographical profiling?

Answer 3

• Geographical profiling is a branch of investigative psychology focused on where an offender is likely to be based rather than their personal characteristics
• Geographical profiling works on the assumption that the locations of crimes are not random
• Geographical profiling helps investigators narrow the search areas
• Geographical profiling uses the least effort principle and the circle hypothesis to estimate where an offender is likely to be based

Question 4

What is the least effort principle?

Answer 4

• The least effort principle states that the closest suitable crime scene to the offenders home base is picked
• This means that the offender will commit fewer crimes further away from their base (Distance decay)

Question 5

What is the circle hypothesis?

Answer 5

-The circle hypothesis states that crimes radiate out from the offender’s home base creating a circle

Question 6

What is a marauder?

Answer 6

• A marauder is an offender that commit crimes close to home

- Marauders operate in an area they are familiar with and their crimes form a circle around their usual residence

Question 7

What is a commuter?

Answer 7

-A commuter is an offender that travels away from home to offend

Question 8

What is smallest space analysis?

Answer 8

-Smallest space analysis is Using computer databases to identify patterns to see if a series of offences are linked

Question 9

What is a strength of the bottom-up approach?

Answer 9

• Canter and Larkin found that 87% of 45 of British serial sexual assaulters were marauders
• This supports the circle hypothesis and the idea that choice of the place of the crime is a significant factor in offender behaviour

Question 10

What is a weakness of the bottom-up approach?

Answer 10

• It is difficult to know if a criminal is a marauder or a commuter before they have been apprehended
• Also it can be difficult to distinguish offences by separate offenders, the number of offenses could be small or not all of the offences recorded

Question 11

What is a strength of the bottom-up approach?

Answer 11

-The bottom-up approach makes inferences based on statistical analysis from published research, it is seen as more scientific than top-down which relies on intuition and experience of the individual criminal profilers

Question 12

What is a weakness of the bottom-up approach?

Answer 12

• All profiling methods suffer from the problem of statistically abnormal offenders
• These people’s behaviour wouldn’t match what would be expected by intuition, based on experience or by considering what is statistically probable behaviour
• This is a problem because both methods are based on previously solved cases of offenders who have actually been caught whereas some criminals do not get caught as they show statistically abnormal offending behaviour