Forensic Psychology L1 - 4 Flashcards
Why is offender profiling used?
To narrow down the list of likely suspects for a crime
What is offender profiling?
Characteristics of offender can be deduced from details of the offence and crime scene
What do profiling methods usually involve?
Careful scrutiny and analysis of evidence
Top-down approach:
1) Templates of organised and disorganised offender are pre-existing in profiler’s mind
2) Evidence from crime scene are then used to fit the offender into one of these categories
Features of organised offenders:
- Planned crime in advance
- Live in relationships
- High level of control/little evidence left at crime scene
- Often of average intelligence in a skilled occupation
Strengths and weaknesses of top-down profiling: (-5)
- Only applies to crimes involving macabre practices eg murder
- Too small and unrepresentative sample to base a typology system
- Not valid to rely on self-report data from convicted serial killers –> Canter (2004)
- Organised and disorganised distinction is too simplistic –> Holmes (1989)
- No evidence for disorganised type –> Canter et al (2004)
Why is that common offences do not lend itself to top-down profiling?
The crime scene reveals little about offender
Why is top-down profiling too small and unrepresentative to base a typology system on?
The organised or disorganised distinction was developed based on interviews w/ 36 sexually motivated serial killers in USA
What did Holmes (1989) suggest about types of serial killers?
- Visionary serial killer –> kill because God/devil directs them to
- Mission serial killer –> kill to eradicate a grp of ‘undesirable’ ppl
- Hedonistic serial killer –> kill for the thrill
- Power serial killer –> kill to have complete control over victims
Canter et al (2004):
- Analysed data from 100 murders in USA thought to be disorganised/organised killers
- Evidence suggested for organised type but not for disorganised
What is the bottom-up approach and what is its aim?
- Profile is data-driven and emerges as profiler engages in rigorous scrutiny of offence details
- Generate pic of offender
Which theory is grounded in psychological theory?
Bottom-up approach
What is the aim of investigative psychology?
Establish a statistical database of behaviours which occur at crime scene and characteristics of offenders who carry these out
What are these characteristics used to do?
Matched against a database to help determine whether multiple offences are linked and likely to have been committed by the same person
Interpersonal coherence:
The way the offender behaves at the crime scene is similar to how they would in real life
What other variable is crucial to the crime?
Time and place
What does it mean if a criminal has forensic awareness?
They have made an attempt to ‘cover their tracks’
Geographical profiling and the data it includes (3):
Study of spatial behaviour in relation to crime and offenders
- Local crime stats
- Crime scene
- Local transport
What are the two models of offender behaviour and who proposed this?
Canter and Larkin (1993):
- Marauder: An offender who operates from home
- Commuter: An offender who travels a distance away from home
In both models of offenders, what does the spatial pattern of their crime scenes always form?
A circle around their home
Are earlier crimes usually closer of further away from the offender’s home and why is this assumption made?
- Closer
- As an offender becomes more confident, they will travel further away
Strengths and weaknesses of bottom-up approach: (+2, -3)
+ Bottom-up profiling is more scientific than top-down profiling –> more grounded in evidence
+ Can be applied to a variety of offences
- Significant failures
- Ineffective –> Copson (1995)
- Conflicting research evidence –> Kocsis (2002)
What significant failure was there when using the bottom-up approach?
- 1992 –> Rachel Nickell was stabbed 47 times and sexually assaulted in Wimbledon Common
- 2008 –> Robert Napper was convicted after analysing evidence
- However, he had been ruled out early on in the initial investigation because he was several inches taller than the profile had suggested
Copson (1995):
- Surveyed 48 police forces
- Found advice provided by profiler was useful 83% of the time
- But only in 3% of cases did it provide accuarte identification
Kocsis et al (2002):
Chemistry students produced more accurate offender profile than experienced senior detectives, which suggests the bottom-up approach is more common sense than skill
What book did Cesare Lombroso write in 1876 and what did he suggest in this? (3)
- L’Huomo Delinquente
- Criminals were genetic throwbacks: a primitive sub-species who were biologically different to non-criminals
- They lacked evolutionary development
- Their savage and untamed nature would inevitably turn them to crime
How did Lombroso argue that the criminal sub-species could be identified? (6)
They had biologically determined atavistic characteristics:
- Narrow sloping brow
- Strong prominent jaw
- High cheekbones
- Facial asymmetry
- Dark skin
- Extra toes/nipples,fingers
How are murderers described according to the atavistic form? (3)
- Curly hair
- Bloodshot eyes
- Long ears
How are sexual deviants described according to the atavistic form? (3)
- Swollen/fleshy lips
- Projecting ears
- Glinting eyes
What are the lips of fraudsters described as according to the atavistic form?
Thin and ready
What other characteristics do criminals have according to Lombroso? (3)
- Tattoos
- Insensitivity to pain
- Use of criminal slang
What key study did Lombroso conduct?
- Examined cranial and facial features of 3839 Italian living and 383 dead criminals
- Found 40% of criminal acts could be accounted for by the criminal sub-species
Strengths and weaknesses of the atavistic form: (+1, -4)
+ Important shift away from theories based on feeble-mindedness and demonic possession –> greater focus towards biological approach
- Racist undertones towards those of African descent
- Conflicting research evidence –> Goring (1913)
- Findings were not compared to a control grp
- Cause and effect –> just because they have atavistic characteristics doesn’t mean that this caused their criminal behaviour
Lange (1930):
- Investigated 13 MZ and 17 DZ twins
- At least one of twins had spent time in prison
- 10/13 MZ and 2/17 DZ had both twins been in prison
Candidate genes:
Genes responsible for causing specific behaviour
Tilhonen et al (2014):
- Genetic analysis on over 900 Finnish offenders
- Found two genes associated w/ violent crime: MAOA, CDH13
- MAOA: Controls dopamine and serotonin and has been linked to aggression
- CDH13: Linked to substance abuse and ADD (attention deficit disorder)
- Individuals were 13 times more likely to have a history of violent behaviour compared to control grp
What does the diathesis stress model say about the influence of genetics on criminal behaviour?
They influence criminal behaviour but are moderated by the effects of the environment
What characteristic do many convicted criminals have and what have investigations on these individuals shown?
- APD (anti-social personality disorder)
- Neural differences in brains of criminals
What 2 characteristics do people with APD have?
- Reduced emotional responses
- Lack of empathy
What neural differences were found in the brains of criminals and who conducted each?
- Reduced activity in pre-frontal cortex
- 11% reduction in volume of grey matter in pre-frontal cortex –> Raine et al (2000)
- Experience empathy less often
Why do APD sufferers experience empathy less often than normal people and who discovered this?
- Keysers et al (2011)
- Their empathy reactions only activated when they were asked to empathise
- They have a neural switch that needs to be turned on to experience it, whereas in normal people, this is always switched on
Strengths and weaknesses of genetic and neural explanation: (-6)
- Concordance rates are quite low –> allows for other factors
- Concordance rates may be due to shared experiences rather than genetics
- ‘Offending behaviour’ as a term is too vague
- Cause and effect –> are brain abnormalities genetic/signs of early abuse?
- Biological reductionism –> other factors?
- Biological determinism –> what about the law?
