FORENSICS Flashcards
What is offender profiling
behavioural and analytical tool intended to help investigators accurately predict and profile characteristics of unknown offenders
aim of offender profiling
narrow down field of enquiry to a list of likely suspects
What do offender profilers generate
work alongside police to generate hypothesis at to who committed the crime
what to offender profilers compile
compile a profile about the offenders age, race, occupation, motives,etc
process of top-down approach in America
-devised by FBI (1970s)
-utilise data gathered from 36 interviews of sexually motivated serial killers inc Ted Bundy and Charles Manson
-data was categorised into organised and disorganised crime
-each category had certain characteristics meaning future crime scenes could be compared to these to help predict other characteristics and help find the offenders
How do offender profilers achieve this
-utilise crime scenes and other evidence including witness reports to achieve this
What do organised offenders show
-evidence of planning
-target of specific victim
-tend to be socially and sexuallly competent with higher than average intelligence
What do disorganised offenders show
-little evidence of planning
-leave clues
-tend to be socially and secually incompetent with lower than average intelligence
what is it argued about organised and disorganised offenders
they have ‘ways of working’ which are known as modus operandi
organised offender characteristics
-above average intelligence
-controlled even in the attack that looks frenzied
-in skilled/professional job
-mostly married with kids
-well thought of in the community
-organised about attach,bring instruments,escape plan etc
disorganised offender characteristics
-low skills job /unemployed
-social/sexual issues
-frenzied in attacks
-no real plan, impulsive attacks
-probably has a criminal record
-leaves clues at crime scene
-lives close to scene
Constructing an FBI profile
-Data assimilation: profiler reviews evidence from crime
scenes photos, pathology reports etc.
-Crime scene classification: either organised or disorganised
-Crime reconstruction: hypotheses in terms of sequence of
events, behaviour of victim etc.
-Profile generation: hypothesis related to the offender e.g.
age, social class, physical and behavioural characteristics.
+ research support for top-down approach
-support for the
organised category of offender.
-To test this typology, Canter et al, analysed 100 US murders each
committed by a different serial killer using a technique called smallest
space analysis. This identifies correlations across different samples of behaviours and in this instance was able to assess the co-occurrence of 39 aspects of serial killings.
-included things such as torture and restraint, an attempt to conceal the body, the murder weapon used and the cause of death.
This analysis does seem to be a subset of features of many serial killers which match the typology for organised offenders.
-This therefore suggests this typology has some validity.
- Counterpoint to the research support of top-down approach
-However, other studies argued that the organised and disorganised
types are not mutually exclusive as there are a variety of combinations
that occur at a murder scene.
-Godwin, believes that in reality, it is difficult to classify killers as one or
the other believing this should work on a continuum.
-A killer may have multiple contrasting characteristics – for example, may be highly
intelligent but commits a spontaneous murder leaving the body at the crime scene.
+ wider application of top-down approach
- has been adapted to solve other types of crimes including burglary.
-Critics say it can only apply to a certain number of crimes such as
sexually motivated murder, however Meketa demonstrated 85%
burglaries were resolved in 3 states in America through this technique.
-This retained the original organised/disorganised offender typology but also added ‘interpersonal’ and ‘opportunistic’.
Interpersonal – the offender usually knows their victim and steals
something of significance.
Opportunistic – generally inexperienced young offender.
-This therefore suggests that the top down approach has wider
application than it originally illustrated.
- flawed evidence for top-down approach
-it is said to be based on flawed
evidence.
-The FBI worked with the 36 murderers, 25 of which were serial killers whilst the remaining 11 were single, or double murderers - 24 were
classified as organised and 12 as disorganised.
-Their selection was
therefore limited - the sample was not random, small in number as
well as only including murderers. Moreover, there was not a standard
set of questions meaning each interview was different meaning the
findings are difficult to compare.
-This therefore suggests that the top down approach is based on
unscientific evidence.
purpose of bottom-up approach
generate a picture of the offender i.e.
Characteristics, routines, behaviour by using psychological theory and
systematic investigation (evidence found at crime scenes)
difference between bottom-up and top-down approach
Unlike the US top-down approach, the British bottom up does not begin with fixed typologies.
Investigative psychology
Form of bottom up profiling that matches details from the crime
scene with statistical analysis of typical offender behaviour patterns
based in psychological theory
aim of investigative psychology
-to establish patterns of
behaviour that are likely to occur across crime scenes to allow a
baseline for comparison.
-Specific details of an offence, can then be matched against this database to reveal important details about their offender, their personal live and background to determine whether a series of offences are linked in that they are likely to have been committed by the same person.
interpersonal coherence in investigative psychology
Interpersonal coherence – the way an offender behaves at the crime
scene, including how they ‘interact’ with the victim may reflect how
they behave in everyday life.
For example, some rapists need to degrade their victims and maximum
control some rapists apologise through the ordeal. This could link to
the status, and success of their romantic relationships.
how does investigative psychology work
All of the information is acquired and placed into a database .
This will be used to check if the crime scene is familiar with any other
ones
The time and place may be significant, the geographical location could also give clues as to where the offender is living.
stages of investigative psychology
1)Go to the crime scene and collect the evidence
2)Compare the evidence with previous crimes stored in the database
3)Establish if the crime scene is similar with any other ones
4)Create a typology.
Geographical profiling
- A form of bottom up profiling based on the principle of spatial consistency - an offender’s operational base and possible future offences are revealed by the geographical location of their previous crime.
-Crime Mapping - utilising the information about the location of crime scenes to make inferences about the home/base of an offender.
-Based on the principle of spatial consistency – people commit crimes within a limited geographical space.
-Used alongside investigative psychology to create hypothesis to determine the offenders thinking as well as modus operandi.
More on geographical profiling
-Summation is that the perpetrator will stay on to an area they are comfortable with to commit crimes
-Their ‘centre of gravity’ in their home
-crime mapping involves plotting the location of linked crimes to create a ‘jeopardy surface’
-this info can help the police to guess where the perpetrator will strike next
Canter’s circle theory assumption
-Pattern of offending forms a circle around the offenders home
-circle appears with regards to crimes (spatial pattern), the more crimes committed the easier to plot
Canters Circle theory - The marauder
Operates in close proximity to their home base
Canter’s circle theory - the commuter
Likely to have travelled a distance away from their residence
What can canter’s circle theory lead to
Figure out social background, mode of transport , work type etc
(+) bottom up approach - evidence for investigative psychology
-Carter + Heritage identified several common behaviours of offenders from 66 assault cases by using smallest space analysis
-several behaviours identified as common in different samples of behaviour eg use of impersonal language and lack of reaction to victim
-each individual displayed characteristic pattern of such behaviours that can be used to establish whether 2/more offenses were committed by same person (case linkage)
-supports idea that people are consistent with their behaviour
(-) Counter point to evidence for investigative psychology - bottom up approach
-case linkage depends on database which consists of historical crimes that have been solved m
-they were solved perhaps because it was relatively straightforward to link these crimes together
-make this a circular argument
-investigative psychology may tell us little about crimes that have few links between then and therefore remain unsolved
(+) bottom up approach - evidence for geographical profiling
-Canter at al collected info from 120 murder cases involving serial killers in US
-smallest space analysis revealed spatial consistency in behaviour of killers
-location of disposal allowed them to see the circle around the home, esp noticable with those who were murderers
-supports view that geographical info can be used to identify an offender
(-) bottom-up approach - geographical profiling may not be sufficient
-may be reliant on quality of data police can provide
-recording of crime is not always accurate ~75% crimes not even reported to police at first place
-questions utility of the approach that relies on the accuracy of geographical data
-even if this info is correct, antics claim other factors are just as important in creating a profile eg timing of the offence and age and experience of offender
-so geographical info alone may not always lead to successful capture of offender
Atavistic form - historical approach
-Cesare Lombroso in 1876 suggested that criminals were ‘genetic throwbacks’ – a primitive sub species who were biologically
different from non-criminals.
He wrote a book called “L’Uomo Delinquente”, roughly
translated as ‘the criminal man’’.
His suggestion is however hugely criticised today for being
speculative and naïve!
atavistic form - biological approach
- Offenders were seen by Lombroso as lacking evolutionary development, as their savage and untamed nature meant they could not conform to society. Instead, they turned to crime.
-As such, Lombroso believed offenders were caused by genetics
suggesting criminal behaviour was innate.
what does atavistic form consider
-Lombroso believed criminals could be identified by having
specific physiological markers that were linked to particular
offences!
-Individuals were distinguishable by particular facial and cranial
characteristics.
Criminal characteristics -cranial
-Narrow, sloping brows
-Strong, prominent jaw
-High cheekbones
-Facial asymmetry
criminal characteristics - physical
-Dark skin
-Extra toes, nipples and fingers
criminal characteristics - other
-Insensitive to pain
-Used slang
-Had tattoos
-Unemployed
characteristic of murderer
bloodshot eyes, curly hair and long ears
characteristics of sexual deviants
glinting eyes, and swollen, fleshy lips
characteristics of fraudsters
Thin and reedy lips
Lombroso’s research on atavistic form
-Completed an examination of the facial and cranial features of
Italian convicts (383 dead convicts and 3839 living) to conclude there was an atavistic form.
-Concluded 40% crimes are committed by people with atavistic characteristics.
+ atavistic form - Lombroso’s legacy & criticism
-Lombroso is considered to be the ‘father of modern criminology’.
-He is said to have shifted the emphasis in crime research away from moral discourse (suggesting offenders were wicked and weak minded) towards a scientific position (blaming evolution and genetics).
-However, critics of Lombroso describe him as racist due to his atavistic characteristics most likely to be found in those of African descent. This fitted with
the eugenic attitude of the 19th century suggesting his theory is subjective rather than objective, influenced by prejudice.
-Eugenics - the suggestion that it is possible to improve humankind by allowing only
some people to produce children.
- atavistic form - contradictory evidence
- Another physician, Goring, also set out to establish whether
there are any other physical characteristics typical of offenders.
-He completed a comparison of 3000 offenders, and 3000
non-offenders concluding there are no distinct cranial
characteristics. He did however believe offenders had below
average intelligence.
- atavistic form - poor control
-Lombroso failed to control key variables.
-Unlike Goring, he did not compare his sample to non-offenders
thus lacking a control group.
-Confounding variables were also ignored – eg. Demographic
poor social conditions such as poverty and lack of education
could contribute to why offenders tend to be unemployed.
- atavistic form - nature vs nurture
-Lombroso’s suggestion of the atavistic form is biological -
criminals are born, not made (nature).
-However poor diet and poverty could also contribute to the
physical features which is therefore due to nurture.
genetic explanation of offending suggests what
would-be offenders inherit a gene, or combination of genes that predispose them to commit crime
genetic explanation of offending - twin + adoption studies
-Lange (1930) 13 MZ twins and 17 DZ twins where one of the twins in each pair has
spent time in prison. 10 of the MZ twins and but only 2 of the DZ twins had a
co-twin that had also spent time in prison, suggesting a genetic link.
-Christiansen (1977) studied over 3500 Danish twin pairs finding concordance rates
for offender behaviour in 35% MZ twin males and 13% for non-identical twin males,
with slightly lower rates for females, again supporting the view that offending may
have a genetic component. This was supported by Danish police records.
-Crowe (1972) found that adopted children whose biological mother had a criminal
record had a 50% risk of having a criminal record by 18 whereas adopted children
whose biological mother did not have a criminal record only had a 5% risk.
genetic explanations of offending - candidate gene
-Tiihonen completed a genetic analysis of almost 800 Finnish offenders
suggesting that two genes are associate with violent crime.
-MAOA – this regulates serotonin in the brain and has been linked to aggressive behaviour.
-CDH13 – this is linked to substance abuse and ADHD.
-5-10% violent crime in Finland is attributed to these genotypes.
genetic explanations of offending - diathesis stress model
-Offending behaviour is explained by a combination of genetic predisposition (diathesis) and a biological or psychological trigger (stress).
-Being raised in a dysfunctional family or having criminal role models.
