Forensics - Profiling Flashcards
Outline what is meant by offender profiling
Offender profiling aims to create a list of likely suspects for a crime, by narrowing down the possible field of perpetrators.
This is done by professional profilers and the police, who use evidence and the crime scene to generate hypotheses about the characteristics of the killer, such as their age, occupation, and so on.
Outline the top-down approach
- This originated in the US (particularly, the FBI) in the 1970s.
- The characteristics of the crime, and the likely offender, is matched to a pre-existing ‘template’, provided by the FBI.
- A murder could be classified as ‘organised’ or ‘disorganised’. This is then used to guide police investigations.
- The templates suggest that the criminal has a particular way of working (‘modus operandi’ or ‘MO’), which correlates with an aspect of their personality, occupation, or something else about them.
- Templates were created through in-depth interviews with 36 serial killers such as Ted Bundy and Charles Manson.
Outline what is meant by organised offending
- Organised offenders show evidence of advanced planning, and will ‘choose’ particular victims.
- High level of control during crime
- Likely to be socially or sexually competent
- Tend to have above-average intelligence
Outline what is meant by disorganised offending
- With disorganised offenders, the crime (such as a murder) is not pre-planned, but is done on the spur of the moment, perhaps in response to a particular emotional trigger (impulsive).
- Leaves clues behind
- Likely to be socially or sexually incompetent
- Likely to have low intelligence, and be unemployed
Outline how to construct an FBI profile
1) Data assimilation: reviewing the available evidence
2) Crime scene classification: organised or disorganised
3) Crime reconstruction: a hypothesis of what happened
4) Profile generation: a hypothesis of the characteristics of the likely offender- background, personality traits, occupation, and so on
Evaluate the top down approach - limited
The top-down approaches work best for particular types of crime, such as premediated murder, rape, torture and so on.
They work much less well for crimes such as burglary, because the crime scene reveals little about the offender.
Therefore, the top-down approach can only be properly used for certain crimes, so it is limited in its usefullness.
Evaluate the top down approach - personality
The top-down approach relies on the prediction that personality characteristics remain fairly stable over time, sometimes over years or decades.
Therefore, it does not consider that personality may be strongly affected by external factors, reducing the validity of this approach.
Evaluate the top down approach - overlap
The top-down approach may be too simplistic in its categories.
For instance, it would be hard for it to explain a spontaneous killing carried out by an educated, professional person.
It has been suggested that there may by overlap between the ‘organised’ and ‘disorganised’ categories, reducing the validity of the approach.
Outline the bottom-up approach
- Developed in the UK by David Canter.
- The aim is to generate a profile of the offender by looking at the available evidence.
- There are no fixed ‘typologies’ (as in the US system) that will be attempted to be matched to the offender.
Instead, a profile should emerge solely from the evidence of each case.
Outline what is meant by investigative psychology
- Investigative psychology is the bottom-up approach to profiling developed by David Canter, who proposed that profiling can and should be based in psychological theory and research.
- Key assumptions made by this approach include: interpersonal coherence (there is a consistency between the way offenders interact with their victims and with others in their everyday lives); time and place (the time and location of an offender’s crime will communicate something about their own place of residence/employment); and criminal characteristics (characteristics about the offender can help to classify them, which helps the police investigation).
Outline what is meant by geographical profiling
Rossmo (1997) proposed this method, which involves looking at the location of crimes which seem to have been committed by the same offender (‘crime mapping’).
Hypotheses can be generated about what the offender is thinking, how they like to operate, where they live or are basing themselves (‘centre of gravity’), and where they are next likely to commit a crime (known as the ‘jeopardy surface’).
Canter’s ‘circle theory’ proposed two models.
- The marauder operates in close proximity to their home, or an equivalent ‘base’.
- The commuter travels a distance away from their residence.
Patterns of offending usually form circles around an offender’s residence, and this can give insights into whether offences were planned, modes of transport involved, the age of the offender, and so on.
Evaluate statistical techniques in investigative psychology - nature of offense
Canter and Heritage (1990) found that when looking at a particular type of crime (sexual assault), the nature of the offence was correlated with particular types of behaviour (such as the use of impersonal language).
This suggests that statistical techniques can be useful in identifying behaviour patterns, so supporting investigative psychology.
Evaluate geographic profiling - research evidence
Lundrigan and Cantor (2001) found that, in 120 murder cases involving serial killers, the killer disposed of bodies in various locations, which formed ‘centres of gravity’, and their base or residence was always located in the middle of this. This supports the use of geographical profiling in helping determine a killer’s base.
Evaluate the bottom-up approach - scientific
Bottom-up approaches could be argued to be more scientific than top-down, as just the available evidence (alongside statistical analysis and predictions) are used to create a profile, rather than attempting to fit offenders to pre-exiting templates. Therefore, this may be a more valid approach to offender profiling.
Evaluate the bottom-up approach - research
Gary Copson (1995) – surveyed 48 police forces, advice given by profiler useful in 83% of cases, but only led to accurate identification of offender in 3% - not entirely useful approach, limited usefulness
