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OFFENDER PROFILING. DEFINITIONS, APPROACHES & DEVELOPING A PROFILE BIASES & PITFALLS APPLIED PROFILING. * DEFINITIONS *. NO CLEAR DEFINITION - varies between profilers and their approach
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OFFENDER PROFILING DEFINITIONS, APPROACHES & DEVELOPING A PROFILE BIASES & PITFALLS APPLIED PROFILING
* DEFINITIONS * • NO CLEAR DEFINITION - varies between profilers and their approach • BLAU (1994) - ‘A method of helping to identify the perpetrator of a crime based on the nature of the offence and the manner in which it was committed’ • TURCO (1993) - ‘The preparation of a biological sketch gathered from info taken at a crime scene, from the personal history and habits of a victim and integrating this with known psychological theory’ • COPSON (1995) - Police need 4 types of information from profilers; • Type of person who committed crime • How great a threat they pose in the future • The possibility that the case is linked to others • How the police should interview suspects • Only certain crimes for which a profile is useful - usually serious offences • Profiling doesn’t SOLVE the crime, but offers an INDICATION of the type of person who did - narrows the field of investigation • Based on two approaches - Scientific or Clinical; • SCIENTIFIC - Statistical analysis of types of offence, r.ship between characteristics of the offence and the geographical distribution • CLINICAL - Personality theories, underlying psychological processes
* THE FBI APPROACH * • 1978, developed systematic profiling technique in USA, alongside their ability to analyse forensic evidence • Based on a study carried out on 36 convicted serial murderers - sexually orientated crimes. Interviewed then categorised as either organised or disorganised; • Began developing theoretical models • RESSLER (1998) - Crime Classification Manual - assists investigators identifying whether a series of offences was committed by the same offender, and estimating the likelihood of a repeat offence
* The BRITISH APPROACH * • Investigative Psychology, dominated by work of DAVID CANTER, after his involvement in the case of John Duffy - Railway Rapist • Uses similar techniques to FBI - builds up database of previous offenders - 66 sexual assaults by 27 offenders, found 33 common offence characteristics, e.g. Blindfolding, gagging, use of a disguise, aggression etc • CANTER argues these associated activities shed light on how criminal behaves in everyday life - can build a picture of a wide range of factors • Duffy originally 1505th in a list of 2000 suspects but Canter’s profile enabled a prompt police response • Convicted in 1988 for 2 murders and 5 rapes
* DEVELOPING A PROFILE * • HOLMES & HOLMES (1996) - 3 goals that influence how a profile is developed • Social and psychological assessment of offender • Psychological evaluation of possessions found with suspected offenders • Consultation with officials on strategies for interviewing techniques • Forensics and Scene of Crime Officers (SOCOs) collect physical evidence from crime scene; psychologists examine these to determine clues of offender’s personality characteristics etc. They also look at… • The offence - nature of it, multiple victims? More complex = more intelligent offender • Timing - Significant in terms of employment - shift pattern? • Offending site - Where? Opportunistic or planned? Majority of offences close to home • Body deposition site - Where was body left? Visible or hidden? • Pattern of Injuries - Directions of wounds can indicate whether left or right handed • Capture style - How did victim end up with offender? • Sex - Significance of sexual acts performed? • Pattern of Victims - Particular type of person? Was victim known? • Trophies/Souvenirs - What was taken?
* BIASES & PITFALLS * • Only used in a number of crimes - not GENERALISABLE to all crimes • Hard to evaluate the EFFECTIVENESS - few crimes to use/evaluate • If profile is wrong, police will be looking for wrong person - wastes valuable time COPSON (1995) - Evaluating Potential for Profiling • Detectives from 48 UK police forces given questionnaire to determine their attitudes to profiling - covered 184 individual cases - 105 solved, 79 unsolved. Most involved murder, the rest rape, serious sexual assault, arson, abduction • Profiling had been sought in ALL cases for various reasons • RESULTS - Only 14% said profiling helped solve the case • Only 16% directly acted on advice received from profiler • Only 3% said advice led to identification of offender • However, 83% found advice useful to understand the case or confirm own their own opinions • 69% would use profiling again • CONCLUSIONS - Profiling seems to be useful to help understand the case, but not necessarily in terms of catching the offender
* BIASES & PITFALLS * • DOUGLAS (1981) - Reviewed costs and benefits of profiling in USA • Although profiling didn’t lead to apprehension of criminals, the benefits in terms of focusing the investigation, saving time etc outweighed the costs • FINKEL et al (1990) - Compared five groups on their ability to compose a profile • Expert profilers • Detectives with no profiling experience • Detectives with profiling experience • Clinical Psychologist • Undergraduates • Results showed profilers were more accurate than others in the sex offence cases, but detectives without experience were more successful in homicide cases • Suggests police experience is more important than psychological training in certain cases
* APPLIED PROFILING * The Rachel Nickell murder • July 1992, 23yr old Rachel sexually assaulted and battered to death whilst walking dog and 2yr old son on Wimbledon Common in broad daylight • She parked car around 10am and seen 20mins later walking towards the woods. Attack occurred 500 yards from car park. Rachel’s body found 4m from path • Little boy will have witnessed event, but was not harmed • Little forensic evidence, just a shoe print • Out of 100 people in area at time, only 2 saw a man washing hands in stream about 150m from crime scene • Called profiler PAUL BRITTON - interviewed friends, family to find out type of person Rachel was. • First thoughts - As son was unharmed, likely to be unknown to Rachel; unlikely to be a domestic. Nature of attack pointed towards a violent sexual psychopath • Based on past contacts, BRITTON drew profile… • Aged between 20 & 30 • Inability to relate to women in conversation • Sexually dysfunctional • Average intelligence • Singe, isolated lifestyle • Live within walking distance of Wimbledon Common
The Rachel Nickell murder ctd. • The profile was broadcast on Crimewatch and within 4 hrs, 300 calls were received and the name Colin Stagg came up 4 times. He fitted BRITTON’s profile exactly • A witness who saw him a few hrs after the murder said he looked ‘strangely excited’ and he’d told her he’d been on Wimbledon Common • He was arrested immediately but consistently denied his involvement. However, his responses to questions strengthened his match to the police • He was released later as there was no hard evidence • A month later they received a letter written to a woman by Stagg describing a fantasy of having sex with a stranger in a public park • An undercover operation was set up - an undercover policewoman going as Lizzie James claimed she was a friend of the woman who passed on the letter and found his fantasies interesting • Stagg did not admit to the murder but revealed things only the murderer could know • Stagg was arrested and charged with Rachel’s murder • However, the case was thrown out of court as the police had used deceptive techniques to incriminate the suspect, and that the prosecution was based almost entirely on BRITTON’s profile • Stagg was released and Rachel’s killer has since not been found EVALUATIVE ISSUES • ETHICS - The way the police handled the case was unthical - deceptive • VALIDITY - The judge questioned the validity of the profile as it was based almost entirely on intuition • EFFECTIVENESS - Although profiles may be accurate, they don’t always lead to the apprehension of a suspect