Interviewing witnesses

Question 1

LOFTUS AND LOFTUS 1987
(Outline one piece of research into factors which influence the accurate identification of a suspect)
Background

Answer 1

There are many factors that influence the accurate identification of a suspect such as memory ability, how long ago you saw face and if the face was meaningful to them. ‘Weapon focus’ is another factor, where witnesses to a crime focus their attention on a weapon, reducing their ability to remember other details of the crime.

Question 2

LOFTUS AND LOFTUS 1987
(Outline one piece of research into factors which influence the accurate identification of a suspect)
Aim

Answer 2

To see if subjects spend more time focusing on a weapon than an ambiguous object during an interaction and if this provides support for the ‘weapon focus’ effect.

Question 3

LOFTUS AND LOFTUS 1987
(Outline one piece of research into factors which influence the accurate identification of a suspect)
Method

Answer 3

A laboratory experiment.

Question 4

LOFTUS AND LOFTUS 1987
(Outline one piece of research into factors which influence the accurate identification of a suspect)
Participants

Answer 4

36 students aged 18-31 years old from the University of Washington.
Half of the participants were recruited through an advert offering $3.50 for completing the study.
The other half were offered psychology credits for completing the study.
Participants believed they were involved in an experiment about ‘proactive interference’.

Question 5

LOFTUS AND LOFTUS 1987
(Outline one piece of research into factors which influence the accurate identification of a suspect)
Procedure

Answer 5

All of the participants were shown a series of slides/pictures of moving through a queue in a Taco restaurant. These slides were identical for both groups except for one slide-IV.

The control group slide showed Person B in the queue handing a cheque over to the cashier
The experimental group slide showed Person B pulling a gun on the cashier.

Each slide was shown for 1.5 seconds. These different depictions of Person B were the dependent variable as participants were later asked to identify this person. This was measured using 20 multiple choice questions which included seven questions related to the appearance of Person B. A line up test of 12 photos was used to identify person B followed by them giving a confidence rating of 1-6 (1=guess; 6= very sure).
The participants‘ eye fixations were also measured to see what part of the slides they focussed on the most.

Question 6

LOFTUS AND LOFTUS 1987
(Outline one piece of research into factors which influence the accurate identification of a suspect)
Results

Answer 6

• Answers to the questionnaire showed that participants in the experimental group were only slightly less accurate than those in the control group.
• In the control group, 7 people (38.9%) were able to correctly identify Person B whereas only 2 in the experimental group (11.1%) were able to. Both groups however showed the same level of confidence in their answers.
• Eye fixation readings showed that as expected, the gun was focused on more than the cheque (3.72 seconds: 2.44 seconds).

Question 7

LOFTUS AND LOFTUS 1987
(Outline one piece of research into factors which influence the accurate identification of a suspect)
Conclusion

Answer 7

Participants focused more on a weapon during an interaction, This led to them being less able to identify the perpetrator from a questionnaire and a line up. This shows that information from witnesses may not be reliable and suggests that any crime involving a weapon may alter the ability to identify or create a reconstruction of a suspect’s face.

Question 8

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Background

Answer 8

E-FIT are computer based composition systems that enable a composite to be created by a trained operator, based on witness descriptions. Features are chosen from a database and combined with Evo-fit images, creating a composite with internal and external features, making it holistic.

Question 10

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Aim

Answer 10

To investigate the recognisability of internal and external features of the face using composites.

Question 10

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Experiment 1 participants

Answer 10

30 staff and students from Stirling University, paid $2.

Question 11

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Experiment 1 procedure

Answer 11

Independent measures design with 3 conditions. All of the participants were given target photos of 10 celebrities and 40 composite images produced by E-fit, Profit, Sketch and EvoFit. The task was to match the target photos of celebrities with the correct composites.
Group One were given complete composites
Group Two were given composites of internal features
Group Three were given composites of external features
Participants were given an unlimited time to complete this task but once the composite was placed on the target photo, it could not be moved.

Question 12

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Experiment 1 results

Answer 12

31% of the composites that were complete and with external features were matched correctly. Only 19.5% of those with internal features were identified correctly.

Question 13

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Experiment 2 participants

Answer 13

48 undergraduates from Stirling University, volunteered to take part in this study.

Question 14

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Experiment 2 procedure

Answer 14

The task was to match a celebrity photo from an array with one of 40 composites shown to the participants. The photo arrays were split into easy (all very different) or hard (with distracter faces).
The participants were then split randomly into four groups:
Easy-internal features
Hard- internal features
Easy-external features
Hard-external features
The composites were presented one at a time along with the photo array of celebrities for participants to match.

Question 15

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Experiment 2 results

Answer 15

Composites of external features were identified much better than those of internal features (41.6%:28.4%)

Question 16

BRUCE AND FROWD 2007
(Describe how researchers have used E-FIT to investigate face recognition)
Conclusion

Answer 16

This research shows that external features are more recognisable than internal features. It also suggests that faces are processed more holistically than by focusing on specific features such as the nose for example.

Question 17

FISHER AND GEISELMAN 1989
(Describe the use of the cognitive interview technique when interviewing witnesses)
Background

Answer 17

Cognitive interview was developed by Fisher and Geiselman. It uses the following procedure:
1. Context Reinstatement
Witness asked to mentally recreate the incident, along with any emotional responses.
2. Focused retrieval
The witness must recall everything even if it seems trivial.
3. Extensive retrieval
Witnesses put themselves in the place of others at scene to change their perspective.
4. Change order
Recalling events in an unusual order may help recall things they may not have otherwise remembered. This can disrupt context reinstatement though.

Question 18

FISHER AND GEISELMAN 1989
(Describe the use of the cognitive interview technique when interviewing witnesses)
Aim

Answer 18

To compare experienced detectives’ interview techniques pre and post cognitive interview training.

Question 19

FISHER AND GEISELMAN 1989
(Describe the use of the cognitive interview technique when interviewing witnesses)
Participants

Answer 19

16 detectives with at least 5 years experience from Florida.
Seven of these completed the cognitive interviewing course and their performance was compared to nine untrained detectives in the control group.

Question 20

FISHER AND GEISELMAN 1989
(Describe the use of the cognitive interview technique when interviewing witnesses)
Method

Answer 20

Field experiment, longitudinal.

Question 21

FISHER AND GEISELMAN 1989
(Describe the use of the cognitive interview technique when interviewing witnesses)
Procedure

Answer 21

1. All of the detectives tape recorded between 5 and 7 of their standard interviews using their regular technique over a period of four months. A total of 88 interviews were recorded.
2. Two groups were created with one having 4 x 1 hour sessions of training in cognitive interview techniques and the other becoming a control group without further training.
3. After training, the seven detectives who underwent training and 6 of the original 9 in the control group recorded between 2 and 7 interviews. 47 interviews were recorded in total over 7 months.
4. Independent judges from the University of California who were blind to the two conditions, transcribed the interviews and scored them based on relevant, factual and objective statements made.

Question 22

FISHER AND GEISELMAN 1989
(Describe the use of the cognitive interview technique when interviewing witnesses)
Results

Answer 22

• When comparing pre and post training, 47% more information was recorded by those detectives that underwent cognitive interview training.
• Upon comparing the trained group and the control group, it was found that there was 63% more information recorded in the interviews conducted by those who were trained.

Question 23

FISHER AND GEISELMAN 1989
(Describe the use of the cognitive interview technique when interviewing witnesses)
Conclusion

Answer 23

These results show that training of cognitive interviewing techniques increases accuracy of responses from witnesses. Due to the training only covering 4 hours, it could also suggest that it is an easy way to increase this accuracy.