Forensic Psychology Flashcards
(137 cards)
What is offender profiling?
An analytical and behavioural tool that predicts and profiles the unknown characteristics of a criminal. This focuses on narrowing down pre-existing suspects.
Possible details generated:
- Age
- Personality
- Race
- Type of employment
- Religion
- Marital status
- Level of employment
What is the top-down approach.
Based on the interviews of 36 sexually motivated serial killers.
It is known as the typology approach because it examines the crime scene and classifies them as either ‘organised’ or ‘disorganised.’
Profilers look at the crime scene features and match it to pre-existing templates.
Subjective = bc relies on the interpretation of the profiler.
What is a disorganised offender?
Crime is unplanned.
Victim is randomly selected and offender is unlikely to engage with victim.
Sexual acts are performed after death.
Weapons and clues may be found at the scene.
What is an organised offender?
Crime is planned.
Victim is specifically targeted.
Body is transported from the scene.
Weapon is hidden
High intelligence.
Socially and sexually incompetent.
Have a car
Follow their crimes in the social media.
What happens after classification?
Construct a profile from pre-existing templates.
This includes = hypothesising offenders looks, background, habits , beliefs etc
Used to work out a strategy of investigation.
Profilers consider how the offender is likely to react if they are being investigated.
What are the 4 stages to constructing a top down profile?
Data assimilation = gathering crime scene evidence
Crime scene classification = organised/ disorganised?
Crime reconstruction = hypothesis of how events occurred and behaviour of the victim etc
Profile generation = hypothesis about the criminal as a results of other predictions e.g physical features
Why does the the top-down approach have low GENERALISABILITY?
Only applies to particular crimes
Based on the interviews of 36 sexually motivated serial killers = best suited for crime scenes that leave important evidence about the offender e.g rape
Cannot be used = burglary bc ctime scene shows very little about the offender.
Why does the top-down approach have questionable validity?
Canter et al (2004)
Canter et al (2004) = smallest space analysis –> analysed date from 100 murders in the USA.
Looked at the cases with 39 characteristics which were thought to be typical for organised and disorganised offenders.
Findings = Evidence shows distinct organised type but not disorganised –> undermines the classification system as a whole.
Top-down approach = widespread support.
Why does the top-down approach have poor temporal validity?
Alison et al (2002) = approach looks at old-fashioned models of personality. Which thinks bhvr is driven by stable dispositional traits rather than external factors.
Why is a weakness that the classification of the top-down approach is too simplistic?
Various critics argue that there are other types of offenders.
Holmes (1989) = four types of serial killers –> visionary, mission, hedonistic and power/control.
What is the bottom-up approach?
Looks for consistencies in the offender’s bhvr during the crime. No assumption is made until a statistical analysis using correlationa; techniques have been used.
approach heavily relies on computer databases being accurate.
objective and reliable.
Why was the bottom-up approach created?
Canter (2004)
Aim = to test the reliability of the top-down typology by applying them to 100 cases. procedure = content analysis of 100 cases of serial killers. Findings = 2x many disorganised crimes than organised crime were identified --> disorganised = easier to identify.
organised offenders:
70% of cases, the body was concealed
75% of cases, sexual activity occurred.
THERE WERE NO SIGNIFICANT DIFFERENCES BETWEEN ORGANISED AND DISORGANISED.
What was the conclusion of Canter (2004)?
No distinction between organised and disorganise = all crimes has an organised element to them.
distinction = how disorganised they are in their offending bhvr
it would be better to look at the personality differences between offenders.
How is the Bottom-up approach effected?
Anomalous results Not all crimes = reported. EWT Leading questions Data being lost Not all crimes are followed up Human error
What are the two components of the bottom-up approach?
Investigative psychology and Geographic profiling
What is investigative psychology?
Aims = match evidence collected to a crime with statistical (computer) analysis. Considers three factors:
Interpersonal coherence = belief that people’s bhvr is consistent and there will be a correlation crime + daily bhvr.
Forensic awareness = indvdls how have knowledge of forensic measures = avoid exposure e.g serial killers hide the body.
Smallest space analysis = main component. Statistical technique which uses police databases to create profiles. Procedure = patters + consistencies.
What is Geographical profiling?
Centre of gravity and jeopardy surface.
Circle theory
marauders vc commuters.
What is centre of gravity and jeopardy surface?
Plotting previous crimes = locate base of operations and the location offender will offender next.
What is circle theory?
Canter and Larkin 1993
If you plot the points where the crimes have taken place = criminal activity will fit within circle. This is often around usual residence + can give insight into the nature of the attacks.
What is marauders vs commuters?
Circle theory = predict the style of movement adopted by criminals.
Marauders = commit crime near to where they live/work
Commuters = offenders who travel to commit crime. Plotting points help determines which type.
How does the Rachel Nickel case show the failures of the bottom-up approach?
Murderer was ruled out in the 1992 investigation because he was not ‘fitting’ the profile (too tall). Wasn’t until 2008 = Robert Napper was the killer.
The system can’t take anomalies.
How does Patherick (2006) suggest there are drawbacks to the bottom-up approach (geographical profiling)?
Machine reductionist = limits the reliability of the results given by the statistics.
Stated flaws in the circle theory. The base of operations is not always in the middle of the circle and can lead to time wasting in investigations = especially if the offender is a commuter.
The data produced by Geographical profiling = too simplistic.
How does the bottom-up approach have high application show the strengths of the bottom-up approach?
Georgraphical profiling
The smallest space analysis and the principle of spatial consistency can be used over a range of crimes e.g murder and rape as well as burglary.
How does Canter and Heritage’s research (1990) support the bottom-up approach?
Adds validity to investigative psychology.
Content analysis of 66 sexual assault cases. Data examined = smallest space analysis.
Several charcteristics found = use of impersonal language/ lack of reaction to the victim.
Lead to understanding how offenders’ bhvr may change over a series of offences. Shows how statistics are useful.