#yuille

Yuille & Cutshall [1986] is both a Study in Detail, and an example of a field study.

They interviewed real witnesses of a real crime. They used witnesses who had observed a gun shooting incident on a spring afternoon in Vancouver, Canada. A thief entered a gun shop, tied up the owner, and stole money and guns. The owner freed himself and picked up a revolver. He went outside to get the car's registration number, but the thief wasn't yet in the care, and he fired 2 shots at the store owner. The owner, after a short pause, fired all 6 shots from his revolver, and killed the thief. The store owner recovered from serious injury. Witnesses saw the scene from different locations- passing cars, buildings, or in the street.

It was chosen because there were enough witnesses to compare their accounts, the thief was killed [& money and weapons recovered] so there was a lot of forensic evidence to verify witness testimonies and the death of the thief closed the file, so research wouldn't interfere with a case. There were also many visible elements to the scene which meant statements could be compared. Witnesses could be asked about events the police's questioning hadn't focussed on, so the police's questioning wouldn't interfere with the study.

Aims: To record and evaluate witness accounts, examining issues raised by lab research and look at the accuracy and kind of errors made in witness accounts. They wanted to compare interviews immediately at the time, which had been carried out by a police officer, and compare them by those carried out by research staff, which also incorporated misleading questions.

Procedure: 21 witnesses were interviewed after the incident. 20 were contacted, 13 agreed to the research interview- 2 had moved away, 5 didn't want to take part, 1 was the victim who didn't want to relive the trauma.

They had verbatim [word for word] reports of police interviews. Participants had been asked to describe the events in their own terms, and then the officer asked a series of questions to amplify what had been said. The interviews were recorded by hand.

4 or 5 months later, the 13 participants were interviewed, they were recorded and transcribed. They gave an account and answered questions [same procedure followed].

They were asked 2 misleading questions: one about a busted headlight, or the busted headlight. one about the yellow quarter panel or a yellow quarter panel. The off-colour quarter panel was actually blue.

They also asked about the degree of stress witnesses experienced at the time, on a 7 point scale. They were asked about their emotional state before, and problems like sleeplessness afterwards.

They used a careful scoring procedure to compare details from the research interviews with those from the police interviews, and what actually happened. They were divided into action details and description details [description details were further divided into object and people details]. 

There was some difficulty with the scoring.

Results: The police gained more action details and person details, but the researchers gained more object details, and more details overall! This was because they asked things which were of no interest to the police.

There was variation in what the witnesses reported because they'd seen different amounts of the incident.

7 were central witnesses, 6 were peripheral witnesses. Both groups were equally accurate, in the police interviews, 84.56% of the central and 79.31% for the peripheral.

4 or 5 months later, errors were relatively rare and accuracy remained high.

Misleading information had little effect, 10/13 said there was no broken headlight or yellow quarter panel, or that they hadn't seen the detail!

Conclusions: this was the first ever investigation in witness testimony to use real witnesses of a real incident!

It's not easy to generalise because there's only 13 witnesses and one unique event. But it shows that eyewitnesses aren't as inaccurate as lab studies suggest! Most were extremely accurate some time later, possibly due to a memorable and unusual incident.

The researchers suggested they may be investigating flashbulb memory, where a specific and relevant event is recorded in memory in great detail. Direct involvement meant they remembered more, lab studies wouldn't capture this involvement.

Their scoring procedures undermined the accuracy of the results due to the conservative rules.

Efforts to mislead did not succeed- this goes against lab findings! It was found that stress doesn't negatively effect memory. Witnesses had felt more adrenaline than stress, and the stress came later.

They've shown that just because one detail is wrong, doesn't mean that other details are necessarily wrong and it should all be rejected.

Evaluation:

It's a field study- real environment and real situation, it has high validity.

Care was taken to make sure that witness testimonies never altered what actually happened, so the findings seem reliable.

We can't generalise from it, it suggests it might be flashbulb memory which is different from what was tested in the lab experiments. Generalising findings to criticise lab experiments may be unfair.