Interviewing Witnesses: Faces
Intro: various methods have been used to identify criminals including identikit and photofit. drawn sketches produced by the witness were also used.
E-fit contain a large range of computerised features to choose from but still siffer from the problem of being based on recognising individual features. Now however more modern techiniques have fixed these problems called
evoFIT: evoFIT has an arrest rate of about 50%, approximately 10 times higher than traditional methods used. it does not require the eyewitness to have a good recall of the offenders face but only to have seen it clearly. it aims to construct the most indentifiable set of internal features, the central region of the face that is important for recognition.
Interviewing Witnesses: Identification
Intro: estimator variable- factors which affect the accuracy of the witness testimony and can't be controled by the justice system e.g. stress, System Variables- factors which affect the accuracy of the testimony which can be controled by the justice system such as leading questions
Study: Pickel studied the affect of unusualness and threat as possible causes of weapon focus (Loftus). there are 4 possible explinations for weapon focus- 1) simply attending to the weapon 2) taking in all the details but only being able to recal the weapon clearly 3) the weapon has a risk factor 4) the weapon is unusual.
Watched a 2 minute clip in a hair salon where a female game a male money. 5 groups saw a variation of the video wach time- 1) no weapon (nothing) 2)scissors (high threat, low unusualness) 3)handgun (H T, H U) 4) wallet (L T, L U 5) raw chicken (L T, H U) and after 10 minutes were asked to fill out a questionnair about receptionists and the mans appearece. No difference in the description of low threat and high threat conditions, significantly poorer in highly unusual
lt suggests that it is not the threat but the unusualness of the object that attracts the attention
Interviewing Witnesses: Cognitive interview
Intro: We have a better recall if we are in the same place, emotional state and context in which the memory was formed. sometimes our recall is inaccurate as we 'fill in' gaps to form complete memory. The CI (Cognitive Interview) uses the following procedures:
Context reinstatement- interviwee is asked to mentally recreate the context of the incident
Report everything- they are asked to recall as much information as the can no matter how trivial
Change the perspective- they are asked to place themselves in another witnesses or victims shoes
Change the order- asked to start at various points during the event and tell their account of what happened from different points.
l enhance version of the CI- interviewee is made to feel relaxed and unhurried. Questions kept to a minimum and interviwee given an active role. Use of focused memory techniques and use of imagry to increase recall. the interviewer is guided by the witness. Gieselman & fisher conducted a small study in which L.A.P.D watched a film and were asked questions about it 48 hours later. they compared standard interview, CI and hypnosis and found that CI recalled a higher number of correct answer yet a higher number of errors from the questions asked about the film
Interviewing Suspects: Detecting Lies
Intro: Police offenders think they are good at detecting lies based on non verbal clues, however there are many cases such as Ian Huntley which suggest they are actually bad at detecting lies.
Study: Vrij and Mann: Sample: 52 uniformed police officers from the netherlands, 28 M 28 F mean age of 31 years, mean service of 9 years.
Procedure: shown 8 video clips of people asking for the publics help in finding relatives or murderers. 5 clips were of people who were later found to be linked to the crimes the other 3 were not. the policemen had to decide whether 1)they were lying Y/N 2) how configent they were out of 1-7, 3) whether they understood what the person was saying Y/N, 4) any behavioural cues to influence behaviour.
Results: 3 officers were accurate 80% at detecting lies , 25 were 60%, 20 were 40% and one officer was wrong every time. Taking into account chance, you would expect 50% so anything over that was making a correct decision, therefore only 49/52 officers where no more than guessing.
Interviewing Suspects: Interrogation
Intro: UK have the PACE act which limits coercive interrogation and the focus is searching for the truth. While the USA depend on coercive interogation, focusing on the search for a confession.
Study: Inbau's steps of interrogation
1. Direct positive confrontation 6. Handling suspects passive mood
2. Theme development 7. Presenting an alternative question
3. Handling denials 8. Having suspect only relate details of offence
4. Overcoming objections 9. Converting oral into written confession
5. retention of suspect's attention
Interviewing Suspects: False confessions
Type of false confessions: Gudjonsson
Voluntary - They believe they have done it - mental disorder Coerced Internalised - Convinced by police they commited a crime they did not - mistrusts memory I.E Alcohol, head injury etc.
Coerced Compliant - Confesses to a crime they know they did not commit - to escape pressure of situation (coercive interrogation)
Factors: The defendant: Age (young/old vunerable), low IQ etc
Arrest and Custody: Arrested in the middle of night/violently are at disadvantage
Mental/physical state: Highly stressed, anxious, ill or intoxicated
Interrogative factors: Coercive, biased or leading interview tatics
Creating a Profile: Top Down
Intro: Breaking down the system to gain insight, an overview of the criminal first then refine in greater detail - criminals are matched with past criminals
FBI Typologies: Interviews with 36 convicted murderers, 41 rapists.
Type of Murder: Organised: Crime is planned, leaves few clues -high IQ, socially/sexualy competent
Disorganised: Little planning, leaves clues - Lives alone near scene, frightened and confused at time of attack
Type of ******: Power reassurance: Needs to reduce doubt about sexuality, uses less force, tends to reoffend in same area
Power assertive: Reoffences rare, expression of masculinity
Anger retaliatory: Expression of anger towards women, attempt to humilate victim
Anger excitment: sadistic motivation, victim is stranger, keeps records
Creating a Profile: Bottom up
We can use information, previously unpredicted to find a pattern of behaviour that can then be used to make future predictions. Canter found himself working on the case of the 'railway ******' in 1980 and one of the assumptions he made was that where an offender lived could be deduced from where their crimes were comitted.
Circle theory of enviromental range - Identify location byt the study of offences, in over 85% of cases the perpetrator lived within the circle of crime.
Evaluations: Given Canter's reliance on building up a map of offender's crimes, one major problem is knowing which, out of all the offences that might have been committed in a city, are ones committed by the person concerned. Canter has sought to address this by investigating on the basis of victim statements - the way the victims are *****.
Evaluation: Interviewing Witnesses
Evaluation: Interviewing Suspects
Evaluation: Creating a Profile
Validity and Reliability: