Eyewitness Testimony

What is an eyewitness testimony?

• If you witness a crime or an accident, you might have to report what you saw, and your version of events could be crucial in prosecuting someone… But your memory isn’t as accurate as you might think…

Kebbel and Milne (1998):

• The British police and juries place a great reliance on EWT

• Kebbel and Milne carried out a survey and found considerable evidence that people’s faith in eyewitness testimony is misplaced

Eyewitness Testimony can be inaccurate and distorted:

1. Eyewitness testimony (EWT) is the evidence provided by people who witnessed a particular event or crime. It relies on recall from memory

2. EWT includes, for example, descriptions (e.g. hair colour, height) and crime scenes (e.g. time, date, location)

3. Witnesses are often inaccurate in their recollection of events and the people involved. As you can probably imagine, this has important implications when it comes to police interviews

4. Many cognitive psychologists focus on working out what affects the accuracy of eyewitness testimony, and how accuracy can be improved in interviews

Fruzzetti et al (1992)

• Fruzzetti et al suggest that thousands of people are probably wrongly convicted every year based on EWT

• Wells et al- reported on 40 cases in the US where individuals were cleared using DNA

• FFive have been sentenced to death and were awaiting execution

Eyewitness testimony can be affected by misleading information:

• Loftus and Palmer (1974) investigated how EWT can be distorted. They used leading questions, where a certain answer is implied in the question

• For example, the question, ‘How much will prices go up next year?’ is leading, because it implies that prices will go up. A better question would be, ‘What do you think will happen to prices next year?’

Loftus and Palmer (1974)- A study into eyewitness testimony:

Loftus and Palmer carried out two experiments in their study

Experiment 1: Method:

• Participants were shown a film of a multiple-car crash. they were then asked a series of questions including ‘How fast do you think the cars were going when they hit?’ In different conditions, the word ‘hit’ was replaced with ‘smashed’, ‘collided’, ‘bumped’ or ‘contacted’.

Results:

• Participants given the word ‘smashed’ estimated the highest speed (an average of 41 mph); those given the word ‘contacted’ gave the lowest estimate (an average of 32 mph)

Experiment 2:

Method:

• The participants were split into three groups. One group was given the verb ‘smashed’, another ‘hit’, and the third, control group didn’t indicate the vehicles’ speed. A week later, the participants were asked ‘Did you see any broken glass?’.

Results:

• Although there was no broken glass in the film, participants were more likely to say they’d seen it in the ‘smashed’ condition than any other.

Conclusion:

• Leading questions can affect the accuracy of people’s memories of an event

Evaluation:

• This has implications for questions in police interviews. However, this was an artificial experiment- watching a video is not as emotionally arousing as a real-life event, which potentially affects recall. In fact, a later study found that participants who thought they’d witnessed a real robbery could give an accurate description of the robber. The experimental design might lead to demand characteristics, where the results are skewed because of the participants’ expectations about the purposes of the experiment. For example, the leading questions might have given participants clues about the nature of the experiment (e.g. they could have realised that the experiment was about respectability to leading questions), and so participants might have acted accordingly. This would have reduced the validity and reliability of the experiment

A critical role:

• Eyewitness testimony frequently play a critical role in criminal investigations, yet psychological studies suggest it is far less reliable than we might imagine

• Research in the United States has shown that inaccurate EWT is the main factor leading to false convictions. One study estimated that there may be about 10,000 wrong convictions a year through EWT.

• In those cases, an innocent person is imprisoned, and the guilty person is still free

Criticisms:

1. Not true to life, recall is more accurate in real life (Yuille and Cutshall, 1986)

   • They interviewed 13 people who had witnessed an armed robbery 4 months after the crime, despite two misleading questions witnesses provided accurate recall that matched their initial statements- suggesting post-event information may not affect memory in real-life EWT

2. Demand characteristic- very hard to estimate speed so P’s may use any available clue

3 Memory stages:

Eyewitness memory goes through three stages:

1. Witness encodes into LTM details of the event and the people involved.

   • Encoding may be only partial and distorted, particularly and sometimes accompanied by rapid, complex and often violent action

2. The witness retains the information for a period of time. Memories may be lost or modified during retention

   • Most forgetting takes place within the first few minutes

     • Other activities between encoding and retrieval may interfere with the memory

3. The witness retrieves the memory from the storage

   • What happens during the reconstruction of the memory may significantly affect its accuracy

Loftus and Zanni (1975)- A study into leading questions:

Method:

• Participants were shown a film of a car crash. They were then asked either ‘Did you see the broken headlight?’ or ‘Did you see a broken headlight?’. There was no broken headlight shown in the film

Results:

• 17% of those asked about ‘the’ broken headlight claimed they saw one, compared to 7% in the group asked about ‘a’ broken headlight

Conclusion:

• The simple use of the word ‘The’ is enough to affect the accuracy of the people’s memories of an event

Evaluation:

• Like the study by Loftus and Palmer, this study has implications for eyewitness testimony. This study was a laboratory study, which made it possible to control any extraneous variables. This means it’s possible to establish cause and effect. However, the study was artificial (participants were shown a film of a car crash, not an actual car crash), so the study lacked ecological validity

Loftus, Miller and Burns (1978)

• Words used in asking questions can change the answers

• Subjects watched a sequence depicting a car (a red Datsun) that makes a turn and hits a pedestrian

  • 50% saw a STOP sign at the intersection

  • 50% saw a YIELD sign at the intersection

• They asked either a consistent or misleading question: ‘Did another car pass the red Datsun while it was stopped at the _____ sign?’

• Misleading- i.e They saw a stop sign and the question mentioned a yield sign

• 20 minutes later subjects received a recognition test in which they were shown two photographs:

  • One had a stop sign and one had a yield sign. They were then asked which one they had seen

Lindsay (1990):

• Findings: Found that when P’s were told to ignore misleading information in an account of a crime, participants were still affected by the misleading information

• Conclusions: Leading questions change the way information is stored and it isn’t just retrieval

Post-event information:

• The studies indicate that the form of questioning can have a significant impact on witnesses’ answers to the question

• It is possible that post-event information may cause the material to be altered before it is stored, permanently affecting the memory

Misleading:

• One of the main factors affecting the accuracy of memory for an event seems to be what happens after the event takes place

• The memory laid down at time seems to be very weak and subject to distortion

Loftus (1992):

• Misinformation can introduce serious errors in eyewitness recall of the event

• Loftus called this misinformation acceptance, where people accept information after the event and absorb it into their memory for the actual event

Leading questions:

• Loftus et al typically use experimental techniques where P’s are shown a film of an event and then exposed them to post-event information such as leading questions and they are then tested for their memory of the original event

Evaluation:

• Lab experiment

• Loftus used realistic material, but the situation was still artificial

• In real life, witnesses are not prepared so they may not be paying the same amount of attention

• Participants may have been subjected to demand characteristics

• Loftus could not get fully informed consent because she could she was going to ask misleading questions

Factors affecting the accuracy of EWT:

Anxiety:

• In psychology, anxiety is a state of emotional arousal, either a feeling or experience of apprehension or uncertainty, brought on by a real or anticipated threat.

• There is evidence to suggest anxiety has a negative effect on memory as it impairs functioning = making recall of an event poorer.

Loftus (1979)- Weapon focus in EWT:

Method:

• In a study with an independent group design, participants heard a discussion in a nearby room. In one condition, a man came out of the room with a pen and grease on his hands. In the second condition, the man came out carrying a knife covered in blood. Participants were asked to identify the man from 50 photographs

Results:

• Participants in condition 1 were 49% accurate. Only 33% of the participants in condition 2 were correct

Conclusion:

• When anxious and aroused, witness focus on a weapon at the expense of other details

Evaluation:

• The study has high ecological validity, as the participants weren’t aware that the study was staged. However, this means that there are also ethical considerations, as participants could have been very distressed at the sight of the man with the knife

Misleading questions and anxiety don’t always affect EWT:

1. A field study by Yuille and Cutshall (1986) showed that witnesses of a real incident (a gun shooting) had a remarkably accurate memories of the event

2. A thief was shot and killed by police and witnesses were interviewed. Thirteen of them were interviewed. Thirteen of them were invited to be re-interviewed five months later. The recall was found to be highly accurate, even after this time period

3. The researchers had included two misleading questions in the study but these were found to have no effect on the subjects’ answers

4. This study had high ecological validity as it was based on a real-life event. However, the witnesses who experienced the highest levels of stress were also closest to the event- it’s difficult to determine whether proximity or stress contributed to the accuracy of their recall

Ethics:

• Anxiety research raises ethical issues

• The participants in Loftus (1979) were deceived as they were led to believe it was a real situation, this may have caused psychological harm to the participant

• In addition; they did not provide fully informed consent and were not aware of their right to withdraw from the study

• The researchers attempted to overcome this by fully debriefing participants at the end of the study and allowing them the right to withdraw

Strengths:

• One strength of Loftus (1979) is that the research is easily replicable as it was an experiment that maintained high control over the extraneous variables

• A second strength is that Loftus (1979) uses a scientific method, this means that we can state that the IV affects the DV

Anxiety:

• Many researchers have looked at the relationship between anxiety and accuracy in EWT

• Deffenbacher et al 2004 carried out a meta-analysis of 18 studies looking at the effect of anxiety on EWT

• From these studies, there was considerable support for the hypothesis that high levels of stress negatively impacted the accuracy of EWT

However:

• Some studies have found emotional arousal may enhance their accuracy

• Christianson and Hubinette 1993:

  • Questioned 58 real witnesses to bank robberies

  • Those witnesses who had been threatened in some way were more accurate than those who had been onlookers

  • This continued to be true even 15 months later

Yerkes-Dobson Law:

• Deffenbacher - suggests that this contradiction is best explained by the Yerkes-Dodson Law

• This states that performance improves with increased arousal but only to a certain point; then further increases in anxiety lead to a decrease in accuracy.

• This is a curvilinear relationship

• There is not a simple relationship between arousal and accuracy

• Accuracy is poor when arousal is either high or low

• Better under conditions of moderate arousal

The Cognitive Interview was developed to increase accuracy:

• Cognitive psychologists have played a big part in helping to increase the accuracy of eyewitness testimony. As you’ve seen research shows that the accuracy of eyewitness testimony is affected by many factors. The cognitive interview technique (CIT) was developed by Geiselman et al (1984) to try to increase the accuracy of witnesses’ recall of events during police questioning.

• Here’s basically what happens in cognitive interviews

  1. The interviewer tries to make the witness relaxed and tailors his/hers language to suit the witness.

  2. The witness mentally recreates the environmental context (e.g. sights and sounds) and internal context (e.g mood) of the crime scene.

  3. The witness reports absolutely everything they can remember about the crime, even if it feels irrelevant.

  4. The witness is asked to recall details of the crime in different orders

  5. The witness is asked to recall the event from various different perspectives, e.g from the eyes of other witnesses

  6. The interviewer avoids any judgemental and personal comments

Geisalman et al (1986)- The effect of the cognitive interview:

Method:

• In a staged situation, an intruder carrying a blue rucksack entered a classroom and stole a slide projector. Two days later, participants were questioned about the event. The study used an independent group design- participants were either questioned using a standard interview procedure or the cognitive interview technique. Early in the questioning, participants were asked ‘Was the guy with the green backpack nervous’. Later in the interview, participants were asked what colour the man’s rucksack was.

Results:

• Participants in the cognitive interview condition were less likely to recall the rucksack as being green than those in the standard interview condition

Conclusion:

• The cognitive interview technique reduces the effect of leading questions

Evaluation:

• The experiment was conducted as though a real crime had taken place in the classroom- it had high ecological validity. The experiment used an independent group design. The disadvantage of this is that the participants in the cognitive interview condition could have been naturally less susceptible to leading questions than the other group (due to individual differences)

Fisher et al (1987):

• Fisher studied real interviews by experienced detectives over a four-month period

• He found that witnesses were frequently bombarded with a series of brief, direct and closed questions aimed to elicit

• However, the order of these questions often seemed to be out of sync with the witnesses’ own mental representation of the event

• Witnesses were often interrupted and not allowed to talk freely about their experience

• Fisher felt that these interruptions were unhelpful because they broke the concentration of the witness and encouraged shorter answers with less detail

• On the basis of research such as this, Geiselman et al 1985 developed the cognitive interview technique as a more effective tool for police

The cognitive-interview:

• Context Reinstatement:

  • Mentally, visualise yourself back in the setting of the incident

• Report Everything:

  • Report all details from start to finish even if it seems irrelevant

• Changed Perspective:

  • Recall the incident from a different viewpoint, e.g if you were at a bus stop, imagine you were on the bus

• Reverse Order:

  • Recall the incident backwards and forward in time

Main techniques used in cognitive interview:

• Context Reinstatement (CR):

  • Mentally reinstate the context of the event. Recall the scene, the weather, thoughts and feelings at the time

• Report Everything (RE):

  • Report every detail possible even if it seems trivial or irrelevant

• Recall from a changed perspective (CP):

  • Try to describe the episode as it would have been seen from the different points of view

• Recall in the reverse order (RO):

  • Change the order of recall so that the event is reported in different orders, moving backwards and forwards in time

Standard Interview:

• Brief questions - Shorter answers

• Closed questions- Less detailed responses

• Question sequence out of sync

• Direct questions

• Broken concentration

• No free talking

Cognitive Interview:

• Listen to witness

• Pause after each response

• Open questions

• Active listening

• Develop rapport

• Minimising distractions

• Avoid interruptions

• Detailed responses

Koehnken et al (1999):

• A number of subsequent studies have confirmed these findings

• However, Koehnken et al 199 found that with the CI, P’s recalled more incorrect information, than with the standard techniques

• It is suggested that this is because they remember more information overall

Milne and Bull (2002):

• Milne and Bull tested the perception of police by testing all the CI procedures either individually or in combination

• They found that all four of the procedures used singly produced more recall than the standard interview

• However, The most effective combination was CR and RE which supports what practising police officers reported

Stein and Memon (2006):

• Tested the effectiveness of the CI in Brazil. This is the first time it has been done in a developing country

• In Brazil, the current method used is interrogation and torture

• Women recruited from the cleaning staff of a large university were required to watch a video of an abduction

• Compared to their usual method the CI increased the amount of correct information obtained

• In particular, the CI was superior in producing forensically rich information

  • IE a detailed description of the man holding a gun

  • The results suggest that the CI may pave the way for a new approach to interviewing witnesses in Brazil and other developing countries

    • Thus reducing the incidence of miscarriages of justice

Young children:

• This is probably because they find the instructions difficult to understand. However, it can be used effectively with children from about 8 years up

• On balance, the CI has proved very useful in increasing the amount and the accuracy of EWT

Holliday (2003):

• Showed two groups of children aged 4-5 and 9-10 a five-minute video of a child's birthday party. The next day all of the children were interviewed using either a standard interview or a cognitive interview

• The findings showed that the use of the cognitive interview resulted in more correct details being recalled about the video compared to the standard interview

• This suggests that the cognitive interview could be useful for interviewing children