Forensic Psychology Flashcards
Offender profiling, top-down approach:
A strength is research support for an organised category…
- Canter et al looked at 100 US serial killings
- small space analysis was used to assess the co-occurrence of 39 aspects of the serial killings
- this analysis revealed a subset of behaviours of many serial killings which match the FBI’s typology for organised offenders
- suggests that a key component of the FBI typology approach has some validity
Offender profiling, top-down approach:
A strength is real life application/ can be adapted to other types of crime E.g. burglary…
- Meketa reports that top-down profiling has recently been applied to burglary leading to an 85% rise in solved cases in 3 US states
- the detection method adds 2 new categories- interpersonal (offender knows their victim, steals something of significance) and opportunistic (inexperienced young offender)
- this suggests that top-down profiling has wider application than was originally assumed
Offender profiling, top-down approach:
A weakness is Godwin argues that in reality…
- Most killers have multiple contrasting characteristics and don’t fit into one ‘type’
- this suggests that the organised-disorganised typology is probably more of a continuum
Offender profiling, top-down approach:
A weakness is evidence for top-down profiling was flawed…
- Canter et al argues that the FBI agents didn’t select a random or even a large sample, nor did it include different kinds of offender
- there was no standard set of questions so each interview was different and not really comparable
- suggests that top-down profiling doesn’t have a sound, scientific basis
Offender profiling, top-down approach:
Extra: personality…
- the top-down approach is based on behavioural consistency- that serial offenders have characteristic ways of working (their modus operandi) so crime scene characteristics help identification
- Mischel argued that people’s behaviour is much more driven by the situation they are in than by ‘personality’
- suggests that a profiling method based on behavioural consistency may not always lead to successful identification of offender
Offender profiling, bottom-up approach:
A strength for geographical profiling is research support…
- Lundrigan and Canter collated information from 120 murder cases in the US
- Smallest space analysis revealed spatial consistency (a centre of gravity) in the behaviour of killers
- offenders leave home base in different directions when dumping a body but create a circular effect, especially in the case of marauders
- this supports the view that geographical information can be used to identify offenders
Offender profiling, bottom-up approach:
A strength is evidence supports investigative psychology…
However…
- Canter and Heritage conducted an analysis of 66 sexual assault cases using smallest space analysis
- several behaviours were identified in most cases (E.g. using impersonal language). Each individual displayed a pattern of such behaviours, helps establish whether 2 or more offences were committed by the same person (‘case linkage’)
- supports one of the basic principles of investigative psychology (and the bottom up approach) that people are consistent in their behaviour
however - database is made up of only solved crimes which are likely to be those that were straight forward to link together which makes it a circular argument
- suggest investigate psychology may tell us little about crimes that have few links between them and so remain unsolved
Offender profiling, bottom-up approach:
A strength is Copson surveyed 48 police departments and found…
However…
- found that the advice provided by the profiler was judged to be ‘useful’ in 83% of cases
- which suggests it’s a valid approach/investigative tool
however
Doesn’t objectively prove it’s effective (just opinion, not proof)
Offender profiling, bottom-up approach:
A weakness is the same Copson study revealed…
- only 3% of cases led to accurate identification of offender
- Kocsis et al found chemistry students produced more accurate profiles than detectives
- Rachel Nickel case offers a stark reminder of how profiling can be misused (real life consequences)
Offender profiling, bottom-up approach:
A weakness is geographical profiling may not be sufficient in its own…
- recording of crime is not always accurate, can vary between police forces and an estimated 75% of crimes aren’t even reported to the police
- even if crime data is correct, other factors matter E.g. timing of the offence and age and experience of the offenders
- suggests that geographical information alone may not always lead to the successful capture of an offender
Biological explanations, Lombroso’s historical approach:
A strength is Lombroso’s theory changed criminology
- Lombroso (the ‘father of modern criminology’) shifted the emphasis in crime research away from moralistic to scientific.
- Also, in describing how particular types of people are likely to commit particular types of crime, the theory heralded offender profiling
- suggests Lombroso made a major contribution to the science of criminology
Biological explanations, Lombroso’s historical approach:
S/W: the atavistic form suggests that crime has a biological cause, it’s genetically determined
Biological explanations, Lombroso’s historical approach:
A weakness is scientific racism…
- DeLisi questioned whether Lombroso’s legacy is entirely positive
- many of the features that Lombroso identifies as atavistic (curly hair, dark skin) are most likely to be found among people of African descent (basically suggesting that Africans ere more likely to be offenders), a view that fitted the 19th century attitudes (to prevent some groups from breeding)
- suggests the theory might be more subjective than objective, influenced by racist prejudices
Biological explanations, Lombroso’s historical approach:
A weakness is Lombroso’s methods were poorly controlled…
- Lombroso didn’t compare his offender sample with a control group and so failed to control confounding variables
- E.g. modern research shows that social conditions (E.g. poverty) are associated with offending behaviour, which would explain some of Lombroso’s links (E.g. would explain why offenders were more likely to be unemployed)
- suggests Lombroso’s research doesn’t meet modern scientific standards
Biological explanations, Lombroso’s historical approach:
A weakness is evidence contradicts the link between atavism and crime
- Goring compared 3000 offenders and 3000 non-offenders and found no evidence that offenders are a distinct group with unusual facial and cranial characteristics
- he did suggest though that many people who commit crime have lower-than-average intelligence (offering limited support for atavistic theory)
- this challenges the idea that offenders can be physically distinguished from the rest of the population, therefore they’re unlikely to be a subspecies
Biological explanations, genetic and neural explanation:
Explain twin and adoption studies as part of the genetic explanation
- Christiansen studied over 3500 twin pairs in Denmark, finding a concordance for offender behaviour of 35% for MZ males and 13% for DZ males (slightly lower rate for females).
- Crowe found that adopted children who had a biological mother with a criminal record has a 50% chance of having a criminal record by age of 18. Whereas adopted children whose biological mother didn’t have a criminal record only had a 5% risk/chance.
Biological explanations, genetic and neural explanation:
Explain a candidate gene study as part of the genetic explanation
- A genetic analysis of about 800 offenders by Tiihonen et al suggested 2 genes that may be associated with violent crime:
-MAOA gene regulates serotonin and linked to aggressive behaviour (also regulates dopamine) - CDH13 gene linked to substance abuse and ADHD
- the study found that 5-10% of all severe violent crime in Finland is attributable to the MAOA and CDH13 genotypes
Biological explanations, genetic and neural explanation:
Explain a study on people with APD as part of the neural explanation
Raine et al found reduced activity and an 11% reduction in the volume of grey matter in the prefrontal cortex of people with APD compared to controls
(Prefrontal cortex is the part of the brain that regulates emotional behaviour so less activity in the prefrontal cortex means less emotional regulation)
Biological explanations, genetic and neural explanation:
Explain what Keysers found…
- Keysers found that only when offenders were asked to empathise did they show an empathy reaction (controlled by mirror neurons in the brain- will become activated)
- suggests APD individuals do experience empathy but may have a neural ‘switch’ that turns on and off
- in a normal-functioning brain the empathy switch is permanently on
Biological explanations, genetic and neural explanation:
Genetic explanation:
A strength is support for the diathesis stress model of offending
- Mednick et al studied 13,000 Danish adoptees having at least 1 court conviction.
- conviction rates:
-13.5% (biological or adoptive parents had no convictions) - 20% (one biological parent)
- 24.5% (both adoptive and biological parents)
- data suggests that both genetic inheritance and environment influence criminality, supporting the diathesis-stress model of crime
Biological explanations, genetic and neural explanation:
Genetic explanation:
A weakness of twin studies is assuming equal environments
- often assumed that environmental factors are the same for MZ and DZ twins because they experience similar environments
- however, as MZ twins look identical, people (especially parents) tend to treat them more similarly which, in turn, affects their behaviour
- therefore, treated more similarly than DZ’s suggesting conclusions lack validity
Biological explanations, genetic and neural explanation:
Genetic explanation:
A weakness is adoption studies…
Many adoptions occur when children are older and many adoptees maintain contact with biological family, so still environmental influences
Biological explanations, genetic and neural explanation:
Neural explanation:
A strength is support for link between crime and frontal lobes…
- Kandel and Freed researched people with frontal lobe damage, including the prefrontal cortex
- they found evidence of impulsive behaviour, emotional instability and inability to learn from their mistakes
- supports the idea that structural abnormalities in the brain are a causal factor in offending behaviour
Biological explanations, genetic and neural explanation:
Neural explanation:
A weakness is the link between neural differences and APD is complex
- Farrington et al studied adult males with high APD scores
- they were raised by a convicted parent and physically neglected
- these early experiences may have caused the APD and associated neural differences E.g. reduced activity in the frontal lobe due to trauma
- this suggests that the relationship between neural differences, APD and offending is complex and there may be intervening variables
Biological explanations, genetic and neural explanation:
A weakness is biological determinism…
- The biological approach suggests offending behaviour is determined by factors which cannot be controlled so no responsibility
- however, justice system based on individual responsibility
- the identification of possible biological precursors to crime complicates this principle
- suggests we should ‘excuse’ some people but ultimately this isn’t possible because many could claim no responsibility
Psychological explanations, Eysenck’s theory:
A strength is evidence supporting Eynseck’s theory
- Eysenck and Eysenck compared 2070 male prisoner scores on the EPQ with 2422 male controls on measures of E, N and P (across all age groups that were sampled)
- prisoners recorded higher average scores than controls
- this agrees with the predictions of the theory that offenders rate higher than average across the 3 dimensions Eysenck identified