Forensic psychology - 2.2 The case for the defence

Reliable, because the statements were obtained without letting the witnesses share accounts and without the use of leading questions.

Unreliable, because the witnesses were not provided with the opportunity to share accounts.

Reliable, because human memory is very accurate at providing detailed accounts of events.

Unreliable, because the statements were obtained too soon after the crime, when the witnesses would still have been anxious and therefore stressed.

This is correct. The witnesses provided similar evidence about what happened without being able to confer and the information came from their memories rather than being suggested by the detective.

This is incorrect. Witnesses should not be allowed to confer as it is very likely that they will change their accounts as a result.

This is incorrect. We should not expect witnesses to provide very detailed accounts of events, nor be dismissive of those who can only provide a few details.

You may find 2.1 Remembering different aspects of a crime useful.

This is incorrect. The results of research on stress are not clear cut, but do not support the suggestion that violent crimes are too stressful to lead to reliable eyewitness evidence and in general, because we tend to forget more and more as time goes by, it is better to interview witnesses as soon as possible.

Have a look back at 3.2.4 The influence of stress and arousal and 2.1.2 Co-witnessing.

Q2. ‘The interviews with both eyewitnesses provide detailed descriptions that are a very good match for the two men accused.’ This piece of evidence is:

Unreliable, because estimates of height, age and weight are always biased by the witness’s own characteristics.

Reliable, because the witnesses were questioned in a safe environment and not back at the crime scene.

Unreliable, because the same interviewer was used in both interviews, the opinions they formed from the first witness would have then contaminated the memory of the second witness.

Reliable, because a cognitive interview was used and the interviewer avoided influencing or contaminating the memory of the witnesses.

This is incorrect. Although witnesses do tend to use their own weight etc. as an ‘anchor’ it is possible to overcome this problem by asking them to make judgements relative to known people/objects rather than provide numerical estimates.

Have a look back at Week 4.

This is incorrect. Although it is certainly important for witnesses to feel safe, ‘context reinstatment’ suggests that interviewing a witness where the crime happened could actually jog their memory and improve the amount and accuracy of the evidence they provide.

Have a look back at Week 4.

This is incorrect. Although interviewers need to be aware of this problem, it can be overcome by using appropriate questioning techniques and particularly by avoiding leading or suggestive questions.

Have a look back at Week 4.

This is the correct answer.

Have a look back at Week 4.

Q3. ‘The two men were identified by one of the eyewitnesses.’ This piece of evidence is:

Unreliable, because one of the witnesses failed to identify each of the suspects.

Unreliable, because a sequential presentation style was employed.

Reliable, because the parades used unbiased instructions, a sequential presentation and the construction was fair.

Reliable, as the witnesses were close to the perpetrators under good lighting conditions, and according to the ‘Rule of Fifteen’ this will make their identifications accurate.

This is incorrect. Remember that it wasn’t that the other witness identified someone else, but said that they were not sure. Although we need to be very careful indeed when it comes to eyewitness identification evidence, we should not expect every witness to be able to identify every perpetrator.

This is incorrect. Research suggests that a sequential presentation style should lead to less chance of an innocent suspect being identified compared to showing all the images at once (a simultaneous presentation style).

You may find 6.1.1 Simultaneous vs sequential presentation useful.

Correct! Research has shown video parades constructed from a large database (such as the VIPER parade used here) to be fair and they also involve showing the faces one at a time. DS Sund was also careful not to use a biased instruction, but to point out that the perpetrator might not be present in the parade.

You may find 6.3.1 Video identification parades useful.

This is incorrect. The Rule of Fifteen sets out the minimum distance and lighting conditions that are needed, but it does not follow that identification will always be accurate if these conditions are met – particularly not if biased instructions and unfair line-ups are used.

You may find 2.1 Remembering different aspects of a crime useful.

2.2 The case for the defence

Activity 2 Evaluate the prosecution’s evidence (DS Sund’s case)