Forensics Flashcards
What are the two pre-existing typologies of offenders
- Organised offenders
- Disorganised offenders
What is the top-down approach
- A top-down approach (TDA) is used when pre-determined theories or ideas are applied to data - in the case of offender profiling the data comes in the form of the crime scene
- The TDA is also known as the American approach to offender profiling as it was developed, primarily, by the American FBI
- The TDA was based on interviews conducted with 36 violent offenders, which included some notorious serial killers who mainly committed sexually motivated murders
Characteristics of an organised vs unorganised offender
What are the personality traits of an organised offender
- are likely to have a high IQ and be in a professional or skilled occupation
- are socially competent and have several friends and colleagues
- are likely to be in a relationship
- may have been suffering from some kind of negative mental state e.g. depression, anxiety, anger when the crime was committed
- are aware of media interest in and coverage of the crime (some offenders may even communicate with the police or media as a way of prolonging their involvement in the crime)
What are the personality traits of a disorganised offender
- are likely to have a low IQ and be in an unskilled or semi-skilled occupation (or unemployed)
- are socially incompetent with few friends and colleagues
- are likely to live alone or have a problematic relationship history
- are likely to have been abused as a child
- are likely to show confusion, fear and panic at the crime scene and in general when confronted with stressful situations
- are more likely to live near the crime scene
Offender profiling def
A behavioural and analytical tool that is intended to help investigators accurately predict and profile characteristics of unknown criminals
What are the 4 stages of constructing an FBI profile (according to the top-down approach)
Evaluation of the top-down approach
- only applies to particular crimes (rape, arson) and not more common offences (burglary and destruction of property). So is a limited approach so lacks generalisability
- the approach is based on an outdated model of personality which sees behaviour as being driven by stable dispositional traits, rather than external factors that may be constantly changing. Therefore it is likely to be outdated and may lack validity when it comes to identifying possible suspects and trying to predict their next move.
- The TDA is based on interview data from 36 serial killers in the 1970s which means that it lacks temporal validity and may suffer from several types of bias (e.g. social desirability bias, confirmation bias) which would damage the validity of the approach
Describe the bottom-up (or British) approach and how investigate psychology fits into this
- The bottom-up approach to offender profiling contrasts to the top-down approach as developed by the FBI in the USA as it is ‘data-driven’
- ‘Data-driven’ means that the BUA does not begin with the assumption that each crime will fit into a typology; instead it uses the crime scene as the basis for the creation of a profile
- The BUA is inductive as it aims to develop a theory from the data presented
- The BUA starts the process of profiling using small, possibly seemingly irrelevant details from the crime scene and uses them to create the ‘bigger picture’, making no assumptions as to the offender
- The BUA is popularly known as the British approach to profiling as it was devised by a British researcher, Professor David Canter
- Canter’s methods involve the cross-referencing of crime-scene details to determine the composition of the offender profile via use of statistical methods, known as investigative psychology (IP)
- The statistical system used in the BUA is known as ‘smallest space analysis’ using evidence from the crime scene which finds a correlation of the behaviours that occurred most frequently across offences
Describe the assumptions made in investigate psychology
- Investigative psychology is the bottom-up approach to profiling developed by David Canter
- 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);
criminal characteristics (characteristics about the offender can help to classify them, which helps the police investigation).
Describe geographical profiling
- Geographical profiling (GP), also known as ‘crime mapping’ is a key aspect of the BUA.
- GP is used to analyse the geographical locations of offences which appear to be linked (committed by the same offender)
- GP can be used alongside investigative psychology to develop a profile as together these two systems form a complete picture of the likely offender
- GP operates along the assumption that serial offenders fall into two categories: marauders or commuters
- Marauders commit crimes within their neighbourhood, not far from where they live/work possibly as this is where they feel safe plus they are more likely to know the escape routes to exit the scene as quickly as possible
- Commuters commit crimes away from their neighbourhood which may be as a result of travelling a lot for work or as a way of avoiding detection
Evaluation of the bottom-up approach
- Much research - particularly by Canter (alone or with colleagues) supports the effectiveness of the BUA in identifying and (more importantly) apprehending dangerous offenders
- The BUA takes a more objective approach than the TDA (which uses as its basis the results of interviews conducted over 50 years ago) with its use of statistical methods which means that it is more reliable than other approaches to profiling
- Kocsis et al. (2002) tested the profiling skills of various police professionals compared to a sample of Chemistry students: the Chemistry students produced the most accurate profiles (interestingly the more experienced the police professionals were, the more inaccurate their profiles were) hence profiling may involve little more than guesswork
- When profiling goes wrong it can be catastrophic: British psychologist Paul Britton’s profile of the killer of Rachel Nickell completely derailed the police investigation and resulted in the murderer going on to claim more victims
What is an atavistic form (the biological explanation of offender profiling)
A biological approach to offender profiling that explains criminal activity as being a result of poor genetics. It suggests that offenders are a primitive sub-species which may have lacked evolutionary development. This is why they are unable to copy with the demands of a civilised society and inevitably turn to crime.
The approach suggests that offenders can be identified by certain facial features such as curly hair, long ears and glinting eyes.
Describe the Atavistic form as founded by Lombroso
– Lombroso founded the atavistic form which historically moves criminology into a more rigorous and scientific realm and his ideas may have laid the foundation for the modern offender profiling techniques (Top down and bottom up approach)
– Lombroso determined atavistic characteristics that make criminals different from the rest of us – these included murderers having bloodshot eyes, curly hair and long wears – sexual deviants had glinting eyes, swollen fleshy lips and projecting ears – and fraudsters were thin.
– Lambroso’s research: Lambroso examined the facial and cranial features of thousands of Italian conflicts, both living and dead, and proposed that the atavistic form was associated with a number of physical anomalies which are key indicators of criminality. He concluded that 40% of criminal acts could be accounted for by atavistic characteristics. He didn’t use a control group to compare.
What are examples of the atavistic characteristics as suggested by Lambroso
- dark skin
- facial asymmetry
- high cheekbones
- insensitivity to pain
- use of criminal slang
- tattoos
- unemployment
MURDERERS:
- Bloodshot eyes
- Curly hair
- Long ears
SEXUAL DEVIANTS:
- Glinting eyes
- Swollen, fleshy lips
Evaluation of the atavistic form as suggested by Lambroso
– A strength of the atavistic form is its contribution to criminology. He is credited to shift the emphasis of crime research away from a more realistic view toward a more scientific and credible realm. In this way his views have had a major contribution to the science of criminology
- the approach can be seen as racist As there are many racial undertones in atavistic features that Lambroso identified. However, some value can be seen in this limitation as it prevents future repetition of racism in research.
- His ideas that offenders struggle to adjust to society is faulty because immigrants may have similar struggles, yet they do not usually turn to crime.
– There is poor control in Lambroso’s research. Lambroso did not compare his criminal sample with a non-criminal control group. It is possible that, if he had done so, the significant differences in atavistic form that Lambroso reported may have disappeared. Many of the criminals he studied had suffered from a history of psychological and physical disorders which may have altered the findings and these were not taken into account.
Contradictory study to Lambroso’s atavistic form
Genetic definition
Genes are inherited and they affect DNA. DNA instruct our physical makeup. This includes brain structure, which affects intelligence, thought patterns and other psychological processes.
Describe the genetic explanations for criminal behaviour
TWIN STUDIES:
-Christiansen (1977) studied 87 MZ and 147 DZ pairs and found a concordance in offending behaviour of 33% for MZs and 12% for DZs
CANDIDATE GENES:
- The MAOA Gene controls dopamine and serotonin production. It has been associated with violent crimes
- The CDHI3 Gene has been linked to substance abuse and ADHD.
- Tilhohen et al (2014) did a genetic analysis of 800 offenders and found that 5-10% of all violent crimes in Finland were due to these genes.
DIATHESIS-STRESS MODEL:
- if genetics have an impact on offending, it is likely that this is at least partly influenced by the environment. A tendency towards criminal behaviour may come about through the combination of genetic predisposition and a trigger such as being raised in a dysfunctional environment or having criminal role models.
- Diathesis: Biological factors (e.g. genes, biochemistry), Psychological factors (e.g. Unconscious conflicts)
- Stress: Biological factors (e.g. poor diet, use of drugs), Social factors (e.g trauma), psychological factors (e.g. violation of trust)
Describe the neural explanations for criminal behaviour
PREFRONTAL CORTEX:
- This cortex is associated with emotion and empathy
- Raine et al: reported several brain images of offenders with APD having less developed prefrontal cortexes. There was a 11% reduced grey matter in the prefrontal cortex.
AMYGDALA:
- The most important part of the limbic system for many emotions, including aggression.
MIRROR NEURONS:
- Allow us to have empathy
- Switched on by default
- Keysers et al (2011): found that criminals could only empathise when told to. So people with APD can have empathy, but do so sporadically and by ‘choice’
Neural explanation definition
Any explanation of behaviour (and its disorders) in terms of (dys)function of the brain and nervous system. This includes the activity of brain structures such as the hypothalamus, and brain structures such as serotonin and dopamine