Improving the Accuracy of EWT

How is EWT inaccurate?

Numerous research studies have indicated that EWT lacks accuracy due to factors such as anxiety, leading questions and post event contamination

What issues did Fisher find in the standard interview?

• Witnesses were given a large number of quick, direct, closed questions in a short time

• The order of questions were not asked in a way that matched witnesses mental representation

• Witnesses were not able to act freely about their experience and were frequently interrupted

What is the cognitive interview?

The cognitive interview is a range of techniques that Fisher and Geiselman (1985) suggested police interviewers can use in order to improve the accuracy of EWT

What are the 4 features of the cognitive interview? (Fisher and Geiselman 1985)

1. Context reinstatement

2. Report everything

3. Recall from a changed perspective

4. Recall in reverse order

Features of the cognitive interview → Context reinstatement

Mentally returning to the scene of the crime, including physical environment and emotional state. This is based on cue dependent forgetting (context/state)

Features of the cognitive interview → Report everything

All details, even if they seem irrelevant should be mentioned, triggering memories

Features of the cognitive interview → Recall from a changed perspective

Consider/mentally recreate how the crime would be recalled from a perspective of other witnesses/perpetrator. ‘Holistic’ view of event to minimise bias and disrupt schema

Features of the cognitive interview → Recall in reverse order

Recall is switched to different chronology/timelines. Eg from end to beginning, or middle to start. This challenges expectations/schema

What is the enhanced cognitive interview? And features?

Focused on building rapport and making the interviewee comfortable

• Interviewer not distracting witness

• Witness controlling flow of information

• Open-ended questions

• Reminded not to guess and use ‘don’t know’ option when necessary

• Reduce anxiety in witness and getting them to relax

AO3 - Fisher, Geiselman and Amador (1989)

Used a field study to compare 7 detectives trained in CI with 9 detectives using the standard interview. The results showed the CI trained detectives received 47% more information in real interviews after their training and 63% more information than the untrained detectives. This suggests the cognitive interview is effective in enhancing memory, improving information gained by real interviewing police officers operating in the field

AO3 - Kohnken et al (1999)

In a meta analysis of 42 studies including 2500 interviews, found a significant increase in the amount of correct information recalled. However there was also a significant increase in the amount of incorrect information recalled, resulting in a very similar accuracy rate 85% CI and 82% SI. This suggests the CI may be of limited practical use due to increased errors

AO3 - Milne and Bull (2002)

Investigated the effect on recall of each of the four aspects of the CI separately. Each aspect produced a similar level of recall however the context reinstatement and report everything condition produced significantly more correct recall. This suggests no single aspect of the CI is more important, instead its overall effectiveness comes from the combined effect of all techniques

AO3 - CI is time consuming

Requires more time than officers have available especially when conducting a time sensitive case. Also the CI requires significant training, diverting officers from their normal work. These issues mean the CI may not be adopted due to the limited time available to police forces

AO3 - Cost benefit analysis

Considers the effect on the overall justice system and economy of the CI. It may be worth the additional resources invested in training to make a more effective police force, with the CI ultimately reducing crime and its cost to wider society

AO3 - Limited usefulness

The CI is not effective in improving the recognition of suspects in identity parades and from photographs. This means the CI has limited usefulness in a number of common police activities involving witness testimony

AO3 - Not effective with very young children

CI has been found to be effective with older children and adults but not very young children as they are egocentric (can only see the world from their own perspective). Holliday created a modified cognitive interview (MCI) adapted to children’s developmental level, this provided a more accurate testimony in 4 to 5 year old children than a standard interview