Forensic Psychology Flashcards
L1 What is a forensic psychologist?
Forensic psychologists apply psychological theory to criminal investigation to help understand psychological problems associated with criminal behaviour, and the treatment of those who have committed offences.
L1 What is offender profiling and what is it based on?
Offender profiling is a tool employed by the police to narrow down the list of
likely suspects for a crime or crimes.
Offender profiling is based on the idea that the characteristics of the offender can be deduced from details of the offence and crime scene.
L1 Methods of offender profiling
Profiling methods vary, but usually 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 (their age, background, occupation etc.).
L1 What is 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/victim/context are then used to fit the offender into either of the two pre-existing categories.
L1 What is an organised offender
These offenders show evidence of having planned the crime in advance; the victim is deliberately targeted as the killer or rapist has a preference for a certain type of victim. The offender maintains a high level of control during the crime. There is little evidence left behind at the scene of the crime. These offenders tend to be of above average intelligence, in a skilled, professional occupation and are socially and sexually competent. They are often married with children.
L1 What is a disorganised offender
These 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, the body is usually left at the scene and there appears to have been very little control on the part of the offender. The offender tends to be of lower than average intelligence, be 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.
L1 Evaluation top down approach (-)
- The top-down approach has been found to be more useful for serious cases, such as murder, where the crime scene reveals more specific personal details about the person committing the crime than for more common property-based crimes such as robbery.
- 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.
- Top-down profiling was developed based on interviews with 36 sexually motivated serial killers, including Ted Bundy and Charles Manson. Canter (2004) has argued that it is not valid to rely on self-report data from convicted serial killers when constructing a classification system.
- The organised or disorganised distinction is overly simplistic. Holmes (1989) suggests there are four types of serial killer; visionary serial killer (kill because God or the Devil is directing them to), mission serial killer (kill to eradicate a group of people they consider to be undesirable), hedonistic serial killer (kill for the thrill) and power serial killer (kill to have complete control over the victims).
L2 what is the bottom up approach
- developed in UK
- aim is to generate pic of offender including likely characteristics, routine behaviour and social behaviour
- achieve through systematic analysis of evidence left at crime scene
- bottom up approach not begin w fixed typologies like top down instead is data driven and emerges as profiler engages in scrutiny of details of the offence
- bottom up profiling is much more grounded in psych theory than top down
L2 what is investigative psychology ?
- The aim of investigative psychology is to establish behaviours that are likely to occur at certain crime scenes.
- This is done in order to create a statistical database which then acts as a baseline for comparison.
- specific details of offence then matched against database to reveal statistically probable detailes abt offender
- also helps determine whether multiple offences linked and likely to have been committed by same individual
L2 what is key concept of investigative psychology?
- concept of interpersonal coherence (way in which offender acted in crime scene and how interact w victim, may reflect behaviour in everyday situations)
- eg. some rapists may want to control humiliate their victim or some may be apologetic, and this may tell police how offender relates to women generally
- significance of time and place of crime is also key variable and may effect where offender lives
- forensic awareness = describes individuals who made an attempt to cover their tracks (hide body or murder weapon or clean crime scene)
- behaviour may indicate they have been subject to police interrogation before or police alr have their dna or fingerprints
L2 what is geographical profiling?
- study of spatial behaviour in relation to the crime and offenders
- focuses on location of the crime as a clue to where the offender lives, works and socialises
- relevant data = crime scene, local crime stats, local transport, and geographical spread o& similar crime
- assume serious offender will restrict criminal activities to an area they are familar with and offenders base will be in middle of spatial pattern of crime scenes
- eg. Earlier crimes are likely to be closer to be closer to the offenders house than later crimes, as becomes more confident, travel further from comfort zones
L2 what are the 2 models of offender behaviour and who developed them?
- Canter and larkin (1993) proposed the two models, one being the marauder, and the other being the commuter
- marauder = offender operates close to their home
- commuter = offender is likely to have travelled a distance away from their home
- spatial pattern of crime will still form a circle around their home, and becomes more apparent more offences committed
- spatial pattern of crimes also tell police whether crime was planned or opportunistic, and other things abt age, mode transport, employment, etc…
L2 + of bottom up approach
+ canter argues bottom up is more scientific than top down as 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.
L2 - of bottom up approach
- There have been some significant failures when using bottom-up profiling. In 1992, 21 year old Rachel Nickell was stabbed 47 times and sexually assaulted in a frenzied attack on Wimbledon Common. 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 (1995) surveyed 48 police forces and found that the advice provided by a profiler was judged to be useful in 83% of cases, but in only 3% of cases did it lead to the accurate identification of the offender.
- Kocsis et al. (2002) 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.
3 key principles in geographical profiling
Least Effort = criminal will not travel further than they have to in order to commit a crime, they usually occur in a criminals locality
Distance Decay = offenders tend to commit more crimes closer to home than further away
Centre of Gravity Hypothesis = where the offender is based will be the place where simultaneously has the minimum possible distance to each of offence locations
