Improving the Accuracy of Eyewitness Testimony: Cognitive Interview (AQA A-Level Psychology): Revision Notes
Improving the Accuracy of Eyewitness Testimony: Cognitive Interview
Introduction
Eyewitness testimony often lacks accuracy, yet such accuracy remains crucial for police investigations and court proceedings. Psychologists have therefore focused their attention on developing methods to improve the accuracy of eyewitness testimony based on sound psychological evidence. The cognitive interview represents one of the most successful contributions psychology has made to society, according to Eysenck and Keane (2010).
The development of the cognitive interview demonstrates how psychological research can be successfully applied to real-world problems, making a meaningful impact on the criminal justice system.
What is the cognitive interview?
The cognitive interview (CI) is a method of interviewing eyewitnesses that helps them retrieve more accurate memories. It employs four main techniques, all grounded in well-established psychological knowledge of human memory:
- Report everything
- Reinstate the context
- Reverse the order
- Change perspective
This approach was developed by Ronald Fisher and Edward Geiselman (1992), who argued that eyewitness testimony could be significantly improved if police used better interviewing techniques based on psychological insights into how memory functions.
The four main techniques
1. Report everything
Witnesses are encouraged to include every single detail of the event, even if it seems irrelevant or the witness feels uncertain about it. This technique recognises that seemingly trivial details may prove important and could trigger other significant memories.
2. Reinstate the context
The witness should return to the original crime scene 'in their mind' and imagine the environment, including what the weather was like, what they could see, and their emotions at the time. This technique relates to context-dependent forgetting - the idea that memory retrieval is enhanced when the context matches that present during encoding.
3. Reverse the order
Events should be recalled in a different chronological order from the original sequence. For example, witnesses might describe what happened from the end back to the beginning, or from the middle to the beginning. This technique serves two purposes: it prevents people from reporting their expectations of how the event must have unfolded rather than the actual events, and it makes dishonesty more difficult (it's harder to fabricate an untruthful account when having to reverse it).
4. Change perspective
Witnesses should recall the incident from other people's perspectives, such as how it would have appeared to other witnesses or to the perpetrator. This technique disrupts the effect of expectations and schema on recall. The schema you have for a particular setting (such as entering a shop) generates expectations of what would have happened, and it's often the schema that's recalled rather than what actually occurred.
The enhanced cognitive interview (ECI)
Fisher and colleagues (1987) developed additional elements of the CI that focus on the social dynamics of the interaction. The enhanced cognitive interview (ECI) includes techniques such as:
- Establishing when to make eye contact and when to relinquish it
- Reducing eyewitness anxiety
- Minimising distractions
- Encouraging the witness to speak slowly
- Asking open-ended questions
These enhancements recognise that the interviewing process itself can affect the quality of information retrieved, highlighting the importance of creating an optimal environment for memory recall.
Evaluation of the cognitive interview
Strengths
Research support for effectiveness
The enhanced cognitive interview has strong research support. A meta-analysis by Köhnken et al. (1999) combined data from 50 studies and found that the enhanced CI consistently provided more correct information than standard police interviews. This demonstrates real practical benefits for police work, giving officers a greater chance of catching and charging criminals, which benefits society as a whole.
Research Finding: Meta-Analysis Results
Köhnken et al. (1999) conducted a comprehensive review of 50 studies and found:
- Enhanced CI consistently outperformed standard interviews
- Significant increase in correct information retrieval
- Practical benefits for law enforcement agencies
Some elements more valuable than others
Research by Milne and Bull (2002) found that each individual CI element was equally valuable, with each technique used alone producing more information than standard police interviews. However, they discovered that using a combination of 'report everything' and 'context reinstatement' produced better recall than any of the other conditions. This finding increases the credibility of the CI amongst police officers by suggesting that even if the full CI isn't used, these two elements should be implemented to improve eyewitness interviewing.
Flexibility of the technique
The CI demonstrates significant flexibility, allowing it to be adapted to different circumstances and overcome objections from those who would benefit most from it - police officers. This adaptability gives the technique greater face validity, as it can be modified to work effectively in various contexts.
Weaknesses
Time-consuming nature
Police may be reluctant to use the CI because it takes considerably more time than standard police interviews. Additional time is required to establish rapport with witnesses and allow them to relax. The CI also requires special training, and many police forces have been unable to provide more than a few hours of training (Kebbell and Wagstaff, 1996). This means the 'proper' version of the CI is unlikely to be used, which may explain why police have not been particularly impressed by it.
Variations in implementation
Studies evaluating the CI's effectiveness inevitably use slightly different techniques or employ the enhanced CI, and the same variation occurs in real-life police work. This makes it difficult to compare different applications of the CI and provides ammunition for police officers to reject it by arguing 'it'll never work here'. However, this variation also represents a strength, as the CI's flexibility allows it to be adapted to overcome specific objections and circumstances.
Increase in inaccurate information
While the CI techniques aim to increase correct information recall, they may also increase the recall of incorrect information. Köhnken et al. (1999) found an 81% increase in correct information but also a 61% increase in incorrect information (false positives) when the enhanced CI was compared to standard interviews. However, the CI is based on solid psychological research into human memory function and should not be abandoned. The increase in accurate recall outweighs any increase in inaccurate information, and efforts should focus on improving the technique rather than abandoning it.
Key Points to Remember:
- The cognitive interview uses four main techniques: report everything, reinstate context, reverse the order, and change perspective
- The enhanced cognitive interview (ECI) adds social dynamics elements like reducing anxiety and asking open-ended questions
- Research consistently shows the CI produces more correct information than standard police interviews
- The combination of 'report everything' and 'context reinstatement' appears most effective
- Main limitations include being time-consuming and potentially increasing inaccurate information alongside accurate recall
- The CI's flexibility allows adaptation to different circumstances, making it more practically viable