Forensic psychology Flashcards
What is the main aim of offender profiling?
To narrow the list of likely suspects
What are the two types of offender profiling?
- Top-down approach
- Bottom-up approach
Give an overview of the top-down approach (4)
FBI
Crime scene
Violent crimes
Pre-existing typologies
- The FBI were the first to use this approach in the 1970s
- The profiler uses evidence at the crime scene to develop a profile of the likely offender
- Most often used in violent crimes, such as murder
- This is then compared to pre-existing typologies to assign the criminal to one of two categories - organised or disorganised offender
Top-down approach - what have the pre-existing typologies come from? (2)
- The FBI interviewed 36 sexually-motivated murderers and used this data, together with characteristics of their crimes, to create two categories (organised and disorganised)
- If the data from a crime scene matched some of the characteristics of one category we could then predict other characteristics that would be likely
Top-down approach - the organised and disorganised distinction is based on the idea that offenders have a certain what?
Modus operandi (set way of working), which usually relates to certain social and psychological characteristics
Top-down approach- what are organised offenders characterised by? (4)
- Evidence of planning the crime - victim is deliberately targeted and the killer/rapist may have a ‘type’ of victim
- High degree of control during the crime and little evidence left behind at the scene
- Above-average IQ - may be in a skilled/professional job
- Usually married and may have children
Top-down approach - what are disorganised offenders characterised by? (4)
- Little evidence of planning, suggesting the offence may have been spontaneous
- The crime scene reflects the impulsive nature of the act, e.g. body still at the scene and the crime shows little control on the part of the offender
- Below-average IQ - may be in unskilled work or unemployed
- A history of failed relationships and living alone, possibly history of sexual dysfunction
Top-down approach - what are the four main stages in the construction of an FBI profile?
- Data assimilation - review of the evidence (photographs, pathology reports, etc)
- Crime scene classification - organised or disorganised
- Crime reconstruction - generation of hypotheses about the behaviour and events
- Profile generation - generation of hypotheses about the offender (e.g. background, physical characteristics, etc.)
Give an overview of the bottom-up approach (3)
- The aim is to generate a picture of the offenders’ characteristics, routines and background through analysis of the evidence
- It does not begin with fixed typologies
- Instead, the profile is ‘data-driven’ and emerges as the investigator scrutinises the details of the offence
The bottom-up approach - investigative psychology
Statistical procedures and psychological theory
Interpersonal coherence
- Attempt to use statistical procedures and psychological theory - statistics are used to create a prediction of behaviour that is likely to occur in crimes. Specific details of an offence are matched to this to create details about the offender
- Idea of ‘interpersonal coherence’ is key- how the offender acts during the crime is likely to relate to their actions in non-criminal situations. E.g. murderer who leaves a very neat and tidy crime scene may be obsessively neat and tidy in everyday life
The bottom-up approach - give an overview of geographical profiling (2)
- The locations of crime scenes are used to infer the likely home or operational base of an offender - crime mapping
- Serial offenders restrict their work to areas they are familiar with (spatial consistency). Location can also be used alongside psychological theory to create hypotheses about the offender and their modus operandi
The bottom-up approach (geographical profiling) - what were the two models of offender behaviour that Canter and Larkin (1993) proposed?
- The marauder - operates close to their home base
- The commuter - likely to have travelled a distance away from their usual residence when committing a crime
The bottom-up approach (geographical profiling) - describe the circle theory (Canter and Larkin) (2)
- The pattern of offending locations is likely to form a circle around the offender’s usual residence, and this becomes more apparent the more offences there are
- The offender’s spatial decision-making can provide insight into the nature of the offence - planned or opportunistic, mode of transport, employment status, etc.).
Biological explanations: a historical approach - what did Lombroso suggest? (3)
- Criminals were ‘genetic throwbacks’ - a primitive subspecies who were biologically different from non-criminals
- Offenders lacked evolutionary development. Their savage and untamed nature meant that they would find it impossible to adjust to civilised society and would inevitably turn to crime
- Saw offending behaviour as an innate tendency
Biological explanations: a historical approach - describe atavistic characteristics (4)
- Physiological markers are evident in criminals and are related to different types of crime
- Cranial characteristics - narrow, sloping brow; strong, prominent jaw; high cheekbones; facial asymmetry
- Dark skin, extra toes, nipples or fingers
- Non-physical characteristics - insensitivity to pain, use of slang, tattoos and unemployment
Biological explanations: a historical approach - different types of offenders have different physical characteristics
Murderers
Sexual deviants
- Murderers - bloodshot eyes, curly hair, long ears
- Sexual deviants - glinting eyes with swollen fleshy lips
Biological explanations: Genetic - what do genetic explanations state?
Offenders have inherited a gene or combination of genes that predispose them to commit crimes
Biological explanations: Genetic - twin studies
Twin studies often show a higher concordance rate for criminality in MZ twins compared to DZ twins, suggesting that genes predispose offenders to commit crime
Biological explanations: genetic - what are the two genes that have been found to be linked to violent crimes (3)
- MAOA and CDH13
- MAOA - controls dopamine and serotonin. A mutant version of the gene, MAOA low, means it is unable to regulate dopamine and serotonin. This may be linked to impulsive behaviour, aggression and violent crimes. Only found to have an influence if linked to childhood maltreatment
- CDH13 - involved in the communication between brain cells. Previously associated with substance abuse and ADHD
Biological explanations: Genetic - diathesis-stress model (2)
- If genes have an influence on offending, this influence is likely to be at least partly moderated by environmental factors
- The diathesis-stress model suggests that a tendency to offending behaviour is due to a combination of: genetic predisposition and a biological or psychological stressor e.g. criminal role models or dysfunctional upbringing
Biological explanations: neural - what do neural explanations consider?
How the structure and workings of the brain may be linked with criminal behaviour
Biological explanations: neural - Antisocial personality disorder (APD) (4)
- The prefrontal cortex regulates emotional behaviour
- People with APD have reduced activity in the prefrontal cortex
- Struggle to process emotions and feel empathy
- Many convicted offenders have a diagnosis of APD
Biological explanations: neural - mirror neurons (3)
- Mirror neurons help us with empathy
- Research has suggested that criminals can feel empathy but may have a neural ‘switch’ that turns on and off
- In a normally-functioning brain the empathy switch is permanently on
Psychological explanations of offending behaviour: Eysenck’s theory - three personality dimensions (2)
- Eysenck studied personality and said personality can be represented along three dimensions: introversion-extraversion (E), neuroticism-stability (N), psychoticism-sociability (P)
- These dimensions combine to form different personality characteristics
Psychological explanations of offending behaviour: Eysenck’s theory - innate, biological basis for personality types (4)
- Eysenck suggested personality types are innate and based on the nervous system we inherit
- Extraverts have an underactive nervous system which means they seek excitement and engage in risk-taking
- Neurotic people have a nervous system that responds quickly to stress, this means they are nervous, jumpy and overanxious so their behaviour is difficult to predict
- Psychotic people have higher levels of testosterone - they are cold, unemotional and prone to aggression
Psychological explanations: Eysenck’s theory - what is the criminal personality type a combination of? (4)
The criminal personality type is a combination of extroversion, neuroticism and psychoticism
* Extraverts seek more arousal and thus engage in dangerous activities
* Neurotics are unstable and therefore prone to overreact to situations of threat
* Psychotics are aggressive and lacking empathy