Booklet 3: Collection of evidence (cognitive) (Key research: Memon and…
Booklet 3: Collection of evidence (cognitive)
Background: The collection and use of evidence from witnesses and suspects
Identity Parades (line-ups)
Traditional method of identifying offender is to use this (still used sometimes in the UK). The victim/witness view line up from behind a screen/one way mirror. Asked to identify perpetrator and the people in the line up may be asked to say a specific phrase.
Victim/witness may feel under pressure to choose and intimidated by being in close proximity to perpetrator. Time consuming also.
VIPER system, developed in West Yorkshire late 1990's used by over 20 police forces in UK. Virtual system using images of volunteers compiling video line-up. Watch a DVD of identification parade. 3 minutes the film lasts must be viewed at least twice. Eliminate feelings of intimidation as not in close proximity to suspect cheaper/easier to carry out.
Caution needs to be taken relying on eye witness testimony. Weapon focus decreases accuracy of witness as they concentrate on the weapon in the crime scene so struggle to remember it properly. So don't know what perpetrator looks like. Loftus & Messo (1987) if participants viewed event with a weapon present less accurate in identification compared with those who didn't view a weapon.
Producing an accurate image of someone to fit a witnesses description- photofit this is building a face from a large bank of photographic images. Modern versions involve 'Facial composite techniques' (FCT) e.g FACES, E-FIT and SketchCop, morph facial characteristics as described by witness. FBI still use sketch artists.
In UK, Police and Criminal Evidence Act (PACE) 1984, governs how police carry out investigation. Arrest, detention, interview, interrogation, entry and search of premises, personal search and taking samples of suspects.
Key research: Memon and Highman (1999) A review of the cognitive interview
Review article. The aim to review of the Cognitive Interview (CI) covering 4 themes.
Theme 1: Effectiveness of the components of the CI
4 key concepts of the CI:
1) Witness mentally reconstructs event-
research suggests that recalling sights, sounds, smells, emotions experienced at crime scene is most effective component of CI. Stage been linked to context dependent memory, memory retrieval enhanced when witness is 'taken back' to original encoding environment.
2) Witness is asked to report everything-
This stage useful when police put together the accounts from several witnesses. Each witness may recall slightly different details, placing all together give more accurate account of crime scene.
3) Recall is encouraged from a variety perspectives-
Police officers tended not to use change perspective instruction and some expressed concern about possibility of misleading a witness. Less useful than other components.
4) Retrieval is attempted from different starting points-
Research found more effective to recall in forward order once, followed by reverse order. This has been challenged by other researchers, who say this doesn't collect any more info than recalling twice in forward order. Seems unclear how useful this stage is.
Enhanced Cognitive Interview (ECI)
Communication between interviewer and witness is seen as important (e.g. active listening, open Q's) enhancing memory retrieval. Effectives of CI is a mix of context reinstatement and improved communication techniques. Mental imagery also a feature in aiding retrieval.
Theme 2: Comparison with other interview methods
The Standard Interview:
Early studies, results between SI and CI results were compared. Sensible research strategy givenhH few other techniques widely used when CI first introduced. However, the SI isn't actually standardised so lots of variability between interviewers, make difficult to use comparison group when researching CI effectiveness. There are number of undesirable characteristics associated with SI, e.g. rapid-fire questions and frequent interruptions. CI offers clear advantage from practical view over SI as these aren't present. CI attempts to use cognitive techniques to improve memory.
In a GI witness guided through each step of incident and probed for full description (environment, emotional reactions- like CI). Form image of perpetrator, describe appearance and impressions of him. As CI made up of different techniques, GMI reasonable comparison, however Guided Memory Interview doesn't ask as many questions.
Aim to build rapport with witness, allow witness to give narrative descriptions. Non-interruptive, expansive, confidence building. Many are also present in CI. However are different in cognitive techniques, e.g. doesn't have context reinstatement. CI gains more info than Structured. Provides a good control group for determining role of techniques in CI.
Overall both CI and Structured Interview are better than Standard Police Interview.
Theme 3: Measuring memory performance
The DV in research- how memory is measured. Research mainly lab based. Most common measure % of interview statements are correct/incorrect. Ignore amount/nature of reported info. Doesn't allow for effective measure of how memory operates. Whether pp 'know/remember' whether series of events occured. Also look at relationship between confidence and accuracy but based on experimental research.
Theme 4: Quality of training
Early studies don't specify amount/quality of training needed for CI and some officers show resistance to being trained but can depend on who's doing the training.
ECI places cognitive pressure on interviewer. So quality and quantity of training key to effectiveness as a method for interviewing.
Feedback on interviewer performance after traing important. Limited research into baseline measures is a methodological view.
Overall need to focus on lenth of training, quality of training, background and attitudes towards learning.
- Interviewers should be given adequate training CI (2 day programme) give direct training to a select group of officers. Fisher (1995): police should guide candidates who can be good interviewers toward role of investigative detective and poor to other aspects.
1. The Standard Interview (SI)
Police received very little training in interviewing techniques and been free to ask witnesses/suspects whatever questions feel relevant. Police interrupt and ask short-answer questions- don't allow elaboration. Not in chronological order so didn't match interviewees memory of the event. Not referring to any specific technique.
2. The Cognitive Interview (CI)
Widely used through UK police forces and aims to maximise information given by victim/witness. Maximises the number of potential retrieval routes and benefit from memory overlap and alternate retrieval cures. Technique devised by Fisher & Geiselman 1980's suggested using cognitive interview results in a 30% improvement in recall.
1. Reinstate context-
Mentally reinstating context of event i.e. what could see, hear, smell during the event and how they felt. 'Taking them back' to the event.
2. Report everything-
Asking witness to report everything, regardless of perceived importance of information. Recall ALL facts about the event.
3. Change perspective-
Recalling the event from variety of perspectives e.g. imagining what scene must have looked like from point of view of several characters there at the time.
4. Change order-
Asking witnesses recall the event in various orders: forward, from a significant event or in reverse order
Fisher and Geiselman (1989) studied 16 detectives , 7 trained in CI and 9 as a control group (used SI), training included 4 one hour training sessions. 63% more info recorded by CI.
Geiselman developed Cognitive Interview for suspects (CIS), used to gain info from suspects and maximise opportunity to detect deception. Contains 2 techniques: making a drawing/sketch and re-telling a story in reverse order as it highlights when suspects are lying.
Both SI and CI allow event review without interference of leading questions, but have scrutinise their memory record.Maximising the no. of potential retrieval routes and benefit from overlaps, triggering forgotten details of the events.
3. The Enhanced Cognitive Interview (ECI)
Same 4 stages as the CI but addsa social aspects into the interview improving communication (only talking when a natural stop occurs). Ensuring distractions kept to a minimum, allowing pauses, being sensitive to needs, creating a rapport. Creating an environment that allows increased context reinstatement.
Reid's 9 steps of interrogation
Interrogation different because it's accusatory. Still used by police in USA but no longer allowed to be used in the UK due to introduction of PACE in 1984. Criticised for being unethical interview and increases chance of false confession.
Interview starts investigator telling suspect that there's no doubt of their guilt.
Direct Confrontation-telling suspect they're guilty.
Chance to shift blame (either to someone else or circumstances)- showing sympathy and offering option to blame others.
Never allow suspect to deny guilt- always interrupt suspects when try to claim they're innocent.
Ignore excuses- Ignore reasons and push for a confession
Reinforce sincerity, eye contact, first names
If suspect cries, infer guilt.
Pose 'alternative question'. 2 choices- one more socially acceptable. Bot inferring guilt.
Get suspect to admit guilt in front of witness.
Get a confession signed.
Application: Strategies for police interviews
The PEACE model
consists of 5 elements:
- Planning and preperation
Includes what to consider when planning interview. May plot timeline of events, collate info and set objectives for interview- could be list of 'facts' needing to be verified. Consider practical issues. Including: where interview takes place, if witness under 16 and needs adult present, if witness vulnerable, language barriers. Plans written down.
- Engage and explain
Attempt to build rapport with witness, rather than firing questions at them. Explain purpose of interview.
Gaining interviewee's account, clarfying it and challenging if needed. Give account (no interruptions). Encourage recollection by either Cognitve approach and Conversation management.
Recall and describe event. Close eyes, draw map or sketch or think about feelings to help. Ask to recall again but in reverse order, or frm different persepctive. Can sharpen memory and help with recollection.
Ask subject say what happened. Divide story into sections and ask each section separately to get more detail. Question aspects that contradict or existing information. Present as request for clarification, rather than accusation. Allow explanation.
Interviewers finish interview appropriately. Reinforce rapport and mean witness may speak again at later date. Make sure contact details are exchanged.
Where interviewer needs evaluate what was achieved during interview and how fits into whole investigation. Need to establish whether everything required addressed and if any details to follow up.