Forensic Psychology Flashcards
Offender Profiling
Used to narrow down the list of likely suspects.
Based on the idea that characteristics of the offender can be deduced from details of the offence and crime scene.
Profiling methods involve careful scrutiny of the crime scene and analysis of evidence, including witness reports, in order to generate a hypothesis about the probable characteristics of the offender.
The Top-Down Approach
Templates of organised offender and disorganised offender are pre-existing in the mind of the profiler.
Evidence from the crime scene and other details of the crime are used to fit the offender into either of the two pre-existing categories, and determine the offender as one type or the other.
Organised Offenders
Show evidence of having planned the crime in advance- the victim is deliberately targeted and will often reveal the fact that the killer or rapist has a preference for a certain type of victim.
They maintain a high level of control during the crime and operate with an almost detached surgical precision. There is little evidence left behind at the scene of the crime.
Tend to have above average intelligence, in a skilled, professional occupation and are socially and sexually competent.
They are often married and have children.
Disorganised Offenders
Show little evidence of planning, suggesting the offence may have been spontaneous.
The crime scene tends to reflect the impulsive nature of the attack and the body is usually left at the scene
Tend to be of lower than average intelligence, in unskilled work or unemployed, and often have a history of sexual dysfunction or failed relationships.
They tend to live alone and often relatively close to where the offence took place.
Evaluation of the top down approach to offender profiling
Disadvantages:
1) Top-down profiling only applies to certain crimes (e.g. murder). Common offences, e.g burglary do not lend themselves to top-down profiling because the crime scene reveals very little about the offender.
2) The organised or disorganised distinction was developed based on interviews with 36 serial killers in the USA. Critics have pointed out that this is too small and unrepresentative a sample upon which to base a typology system.
3) Top-down profiling was developed based on interviews with 36 sexually motivates serial killers. Canter argued that it is not valid to rely on self-report data from convicted serial killers when constructing a classification system.
4) The organised or disorganised distinction is overly simplistic. Holmes suggests there are four types of serial killer; visionary, mission, hedonistic, and power
5) Canter analysed data from 100 murders in the USA. The findings did suggest evidence of a distinct organised type, however this was not the case for disorganised type which undermines the entire classification system.
The Bottom-Up Approach
Aim - to generate a picture of the offender, including their likely characteristics, routine behaviour, and social background. This is achieved through systematic analysis of evidence left at the crime scene.
This approach does not begin with fixed typologies. Instead the profile is data-driven and emerges as the profiler engages in rigorous scrutiny of the details of the offence.
Bottom-up profiling is far more grounded in psychological theory than the top-down approach.
Investigative Psychology
Aim - to establish behaviours that are likely to occur at certain crime scenes.
This is done to create a statistical database which then acts as a baseline for comparison. Specific details of an offence can be matched against this database to reveal statistically probable details about the offender. This can also help determine whether multiple offences are linked and likely to have been committed by the same individual.
The way in which an offender behaves at the crime scene (e.g how they interact with the victim) may reflect their behaviour in everyday situations. This might tell the police how the offender relates to women more generally.
The significance of time and place of the crime is also a key variable and may indicate where the offender lives.
Forensic awareness describes individuals who have made an attempt to ‘cover their tracks’. Their behaviour may indicate that they have been the subject of police interrogation in the past, or even that the police already have their DNA or fingerprints on file.
Geographical Profiling
The study of spatial behaviour in relation to crime and offenders.
Focuses on the location of the crime as a clue to where the offender lives, works and socialises.
Relevant data includes the crime scene, local crime statistics, local transport, and geographical spread of similar crimes.
The assumption is that a serious offender will restrict their criminal activities to a familiar area, and the offender’s base is in the middle of the spatial pattern of their crime scenes.
Earlier crimes are likely to be closer to the offender’s base than later crimes. As an offender becomes more confidence they will often travel further from their comfort zone.
Canter and Larkin propose two models of offender behaviour: the marauder (who operates close to their home) and the commuter (who is likely to have travelled a distance away from their home). The spatial pattern of their crime scenes will still form a circle around their home. This becomes more apparent the more offences that are committed.
The spatial pattern of a crime can also tell the police whether the crime was planned or opportunistic, as well as other important facts about the offender such as their mode of transport, employment status, approximate age, etc.
Evaluation of Bottom-Up Approach
Advantages:
+ Canter argues that bottom-up profiling is more scientific than top-down profiling because it is more grounded in evidence and psychological theory and less driven by speculation and hunches than top-down profiling.
+ Bottom-up profiling (unlike top-down profiling) can be applied to a wide variety of offences, such as burglary and theft, as well as murder and rape.
Disadvantages:
- There have been some significant failures when using bottom-up profiling. In 1992, Rachel Nickell was stabbed 47 times and sexually assaulted. In 2008, following examination of forensic evidence, Robert Napper was convicted of the murder. He had been ruled out early on in the initial investigation because he was several inches taller than the profile had claimed the offender would be.
- Copson surveyed 48 police forces and found that the advice provided by a profiler was judged to be useful in 83% of cases, but only lead to the accurate identification of the offender in 3% of cases
- Kocsis et al. found that chemistry students produced a more accurate offender profile than experienced senior detectives. This implies that the bottom-up approach is little more than common sense and guess work.
Historical Approach to Offending
- Lombroso wrote a book in which he suggested that criminals were genetic throwbacks - a primitive sub-species who were biologically different from non-criminals.
- Offenders were seen by Lombroso as lacking evolutionary development. Their savage and untamed nature meant that they would find it impossible to adjust to the demands of civilized society and would inevitably turn to crime.
- Lombroso saw criminal behaviour as a natural tendency, rooted in the genealogy of those who engage in it.
Atavistic Form (Lombroso)
atavistic - reversion to something ancestral
Criminal sub-species could be identified by particular physiological characteristics that were linked to particular types of crime.
These were biologically determined atavistic characteristics (mainly features of the face and head) which indicate that criminals are physically different from the rest of us.
In terms of cranial characteristics, the atavistic form included a narrow, sloping brow, a strong prominent jaw, high cheekbones and facial asymmetry.
Murders were described as having bloodshot eyes, curly hair, and long ears.
Sexual deviants as having glinting eyes and projecting ears.
Lips of fraudsters were thin and ‘reedy’.
Other than physical traits Lombroso also suggested other characteristics of the born criminal, including insensitivity to pain, use of criminal slang, tattoos and unemployment.
Lombroso examined the facial and cranial features of living and dead Italian convicts and proposed that the atavistic form was associated with a number of physical anomalies which were indicators of criminality. Lombroso examined the skulls of 383 dead criminals and 3839 living ones, and concluded that 40% of criminal acts could be accounted for by the criminal subculture.
Evaluation of Atavistic Form
Advantages:
+ The atavistic form had an important role in the shift away from theories based on feeble-mindedness, wickedness and demonic possession. It was the forerunner to more biological explanations
Disadvantages:
- Several critics have drawn attention to the distinct racist undertones in Lombroso’s work. Many of the features he described as atavistic (e.g. dark skin and curly hair) are most likely to be found in people of African descent. His claim that atavistic characteristics were uncivilized, savage and primitive supported the eugenic philosophy.
- Goring wanted to establish if there were any physical or mental abnormalities among the criminal classes. After conducting a comparison of 3,000 criminals and 3,000 non-criminals he concluded that there was no evidence that offenders had particular facial and cranial characteristics. However, he did suggest that criminals are more likely to have a below average intelligence.
- Lombroso did not compare his criminal sample to a non-criminal control group. If he had done then the differences he reported may have disappeared.
- Even if criminals have atavistic characteristics this not necessarily mean that these characteristics cause their criminal behaviour. Facial and cranial features can be influenced by poverty and poor diet, which can also lead people to crime.
Genetic explanations for crime (AO1) - Introduction + Lange investigation
- would-be offenders inherit a gene/combination of genes, that predisposes them to commit crime.
Lange:
- investigated 13 mz twins and 17 dz twins.
- At least one of the twins in each pair had served time in prison.
- 10 out of 13 pairs of mz twins had both spent time in prison, whereas only 2 of the 17 pairs of dz twins had both spent time in prison.
Genetic explanations for crime (AO1) - polygenetic and Tilhonen study
Criminal behaviour could be polygenic, meaning no single gene is responsible for offending. Instead, many genes might be responsible for causing criminal behaviour (candidate genes)
Tilhonen et al. conducted a genetic analysis of over 900 Finnish offenders. This revealed abnormalities on two genes that may be associated with violent crime.
These were:
- the MAOA gene - controls dopamine and serotonin in the brain and has been linked to aggressive behaviour.
-The CDH13 gene- has been linked to substance abuse and attention deficit disorder.
In the Finnish sample individuals with this high-risk combination of genes were 13 times more likely to have a history of violent behaviour compared to a control group.
Genetic explanations for crime (AO1) - the DSM
The DSM states that genetics influence criminal behaviour but this is moderated by the effects of the environment.
A tendency towards criminal behaviour may come through a combination of genetic predisposition and biological/psychological triggers. E.g being raised in a dysfunctional environment.
Neural Explanations
1)
Evidence suggests that there may be neural differences in the brains of criminals and non-criminals.
Much of the evidence in this area has investigated individuals diagnosed with anti-social personality disorder.
APD is associated with reduced emotional responses and a lack of empathy, a condition that characterises many convicted criminals.
There are several brain-imaging studies which show that individuals with anti-social personalities have reduced activity in the pre-frontal cortex of the brain (regulates emotional behaviour)
Raine et al. found an 11% reduction in the volume of grey matter in the prefrontal cortex of people with APD compared to a control group.
2)
Recent research has suggested that criminals with APD can experience empathy but that they do so more sporadically than the rest of us.
Keysers et al. :
- found that only when criminals were asked to empathise (with a person on a film experiencing pain) did their empathy reaction activate.
- This suggests that APD individuals are not without empathy but may have a neural switch that needs to be turned on in order to experience it.
- In a normal brain the empathy switch is permanently switched on.
Evaluation of Genetic and Neural Explanations
Disadvantages
1) Concordance rates in MZ twins are not high and leave plenty of room for non- genetic environmental factors. Concordance rates may be due to shared learning experiences rather than genetics.
2) Brain scanning studies (e.g Raine et al) show pathology in brains of criminal psychopaths, but cannot conclude whether these abnormalities are genetic or signs of early abuse.
3) The term ‘offending behaviour’ is too vague. Some specific forms of crime may be more biological than others e.g. physical aggression.
4) The genetic and neural explanation of criminal behaiour is an example of biological reductionism. Criminality is complex and explanations that reduce offending behaviour to a gene or imbalanced neurotransmitter may be overly simplistic. Criminal behaviour does seem to run in families, but so does emotional instability, mental illness, social deprivation and poverty. Twin studies never show 100% concordance rates in mz twins, so genetics cannot be the only explanation for criminal behaviour.
5) The genetic and neural explanation of criminal behaviour is an example of biological determinism. This presents a dilemma for our legal system. If someone has a criminal gene they cannot have personal and moral responsibility for their crime. If this is the case it would be unethical to punish someone who does not have free will.
Eysenck’s Theory of the Criminal Personality - General Personality Theory
Eysenck suggested that behaviour could be represented along two dimensions: introversion/ extraversion and neuroticism/stability.
The two dimensions combine to form a variety of personality traits.
He later added a third dimension – psychoticism
According to Eysenck our personality traits are biological in origin and come about through the type of nervous system we inherit from our parents. Therefore, all personality types, including the criminal personality type, have an innate, biological basis.
Extraverts have an underactive nervous system so they are constantly seeking excitement, and stimulation, and may engage in risk-taking behaviour. They are difficult to condition and so do not learn from their mistakes.
Neurotic individuals tend to be nervous and over-anxious, and their general instability means their behaviour is often difficult to predict.
Criminal Personality
The criminal personality type is neurotic-extravert (A combination of all of the characteristics and behaviours of extraversion and neuroticism).
Eysenck suggested a typical offender will also score highly on psychoticism – cold, unemotional and prone to aggression.
In Eysenck’s theory, personality is linked to criminal behaviour via socialisation. Eysenck saw criminal behaviour as developmentally immature in that it is selfish and concerned with immediate gratification. During socialisation children are taught to delay gratification and be socially orientated. Eysenck believed that people with high extraversion and neuroticism scores had nervous systems that made them difficult to condition, as a result they will not learn easily to respond to their anti-social impulses with anxiety. Consequently they are more likely to act antisocially in situations where the opportunity presents itself.
Eysenck developed the Eysenck Personality Inventory, a psychological test which locates respondents along the extraversion and neuroticism dimensions to determine their personality type. A later scale was introduced that is used to measure psychoticism.