Forensic Psychology Offender Profiling Bottomup approach Investigative Psychology

Forensic Psychology Offender Profiling Bottom-up approach Investigative Psychology and Geographical Profiling

Learning Objectives • explain bottom up approach to profiling, investigative psychology and geographical profiling • use research evidence to evaluate the usefulness of offender profiling

Bottom-up approach Two main types of Bottom-Up Profiling • Investigative Psychology • Geographical Profiling

Investigative Psychology • Data driven • Profiling is based on scientific theory and research • Interpersonal coherence (Looking out for correlations in peoples behaviour) • Forensic awareness Certain behaviours deduced from the crime scene analysis may reveal awareness of particular police techniques – which would aid profiling. E. g. Davis et al (1997) found that rapist who conceal fingerprints often had a previous conviction for burglary.

Geographical Profiling Criminals reveal themselves by the locations they choose. A form of bottom up profiling based on the location or locations of a series of crimes. It analyses the spatial relationships between different crime scenes and how they might reveal the offenders place of residence.

Geographical Profiling Criminals reveal themselves by the locations they choose. Circle Theory Canter & Larkin (1993) Offenders have a spatial mindset and they commit crimes in an imagined ‘circle’.

Marauders and Commuters Circle Theory proposes two models of offender behaviour. People operate within a limited spatial mind set that creates imagined boundaries in which crimes are likely to be committed. The Marauder: the offender operates in close proximity to their home base. The Commuters: the offender is likely to have travelled a distance away from their usual residence.

Evaluating the Bottom Up Approach 45 UK Police Forces It is scientific and therefore objective and more reliable. Does not consider the role of ‘personality’ in profiling were surveyed and 75% said that the process was useful! BUT…only 3% said that it actually helped to catch the offender. Is the ‘circle’ theory really a circle? Most offenders are classified as Marauders so is there really a difference. What if their home doesn’t fall into Profiling cannot reliably identify an offender but it the centre of the circle? can help to narrow down.

Comparing the approaches The top-down approach: • Originates in law enforcement expertise. • Is based on qualitative methods and creating hypotheses from scrutiny of the crime scene and witness reports. • Is used mainly for murder and rape. • Focuses on evidence found at the crime scene which is then used to infer. • Work down to assign offenders into categories.

Bottom-up approach: • Originates in psychological expertise. • Is based on quantitative statistical analysis. • Can be used with all types of crimes. • Focuses on the distribution of crimes in an area. • Work up from evidence collected at the crime scene.

Similarities between the top-down and bottom-up approaches: • 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.

Homework Exam Questions 1. Distinguish between the top down and bottom up approach to profiling (4 marks) 2. Evaluate the top down methods of profiling. (4 marks)