Eye Witness Testimony

Take a look at the following article from the Independent. Click on the image for the link to the full article.

Now take a look at these Youtube excerpts by memory expert Elizabeth Loftus

And this…

Eyewitness Testimony

Reconstructive Memory  Bartlett (1932)

Barlett’s theory of  Reconstructive Memory is crucial to an understanding of the reliability of eye witness testimony (EWT) as he suggested that recall is subject to personal interpretation dependent on our learnt or cultural norms and values – the way we make sense of our world.

In other words, we tend to see and in particular interpret and recall what we see according to what we expect and assume is ‘normal’ in a given situation.

Barlett referred to these complete mental pictures of how things are expected to be as Schemas. These schemas may, in part, be determined by social values and therefore prejudice.

Schemas are therefore capable of distorting unfamiliar or unconsciously s ‘unacceptable’ information in order to ‘fit in’ with our existing knowledge or schemas. This can, therefore, result in unreliable eyewitness testimony.

Barlett tested  this theory using a variety of stories to illustrate that memory is an active process and subject to individual interpretation or construction.

Have a go! Read the following story and then remove from screen and attempt to recall it.

The War of the Ghosts.

One night two young men from Egulac went down to the river to hunt seals, and while they were it became foggy and calm. Then they heard war cries and they thought; ‘Maybe this is a war-party.’ They escaped to the shore, and hid behind a log.

Now canoes came up, and they heard the noise of paddles and saw one canoe coming up to them. There were five men in the canoe and they said; ‘What do you think? We wish to take you along. We are going up the river to make war on the people.’

One of the young men said; ‘I have no arrows.’

‘Arrows are in the canoe,’ they said.

‘I will not go along. I might be killed. My relatives do not know where I have gone. But you, ’he said turning to the other, ’May go with them.’

So one of the young men went, but the other returned home. And the warriors went on up the river to a town on the other side of Kalama. The people came down to the water and began to fight, and many were killed. But presently, one of the young men heard one of the warriors say; ’Quick let us go home. That Indian has been hit.’

Now he thought; ‘Oh, they are ghosts.’ He did not feel sick, but he had been shot. So the canoes went back to Egulac, and the young man went back to his house and made a fire. And he told everybody and said; ‘Behold, I accompanied the ghosts, and we went to fight. Many of our fellows were killed and many of those that attacked us were killed. They said I was hit, but I did not feel sick.’

He told it all, and then he became quiet. When the sun rose, he fell down. Something black came out of his mouth. His face became contorted. The people jumped up and cried. He was dead.

According to Barlett your recall will show a westernised interpretation of this American Indian folk tale thus illustrating your subjective memory construction rather than accurate objective recall of events. How might this idea be applied to eyewitness testimony of criminal occurrences.

Reconstructive Memory The work of Loftus in this area, (1974)

Loftus drew on the ideas of Barlett and conducted research illustrating factors which lead to inaccurate recall of eye-witness testimony. Loftus & Palmer (1974) conducted two laboratory experiments to illustrate this reconstrutive memory and how this is influenced by questioning techniques used by the police.

Experiment One

45 participants involved using an independent measures design.

Participants were shown films of traffic accidents.

They were then given a general account of what they had just seen and asked a series of questions about it.

The critical question asked was ‘About how fast were the cars going when they HIT each other?’

OR  the word ‘HIT’ was replaced by either ‘SMASHED’, ‘COLLIDED’, ‘BUMPED’ or ‘CONTACTED’.

The results suggested that participants recall was influenced by the word used – the independent variable. The word ‘smashed’ led to the fastest speed estimate and the word ‘contacted’ the slowest.

Experiment Two

The experiment above could be explained by response bias – pressure from interrogator or a change in participants recall of the event because of word used in question.

Loftus & Palmer conducted this experiment in order to test which explanation was accurate.

150 students were tested using independent measures design.

Participants were shown a short film of a traffic accident.

They were then given a general account of what they had seen. They were then divided into groups of 50.

The first group was asked ‘How fast were the cars going when they hit each other?’

The second group were asked ‘How fast were the cars going when they smashed into each other?’

The third group were not asked the question at all and acted as a control group.

One week later they were asked a series of questions about the road traffic accident, one of which was the critical question, ‘Did you see any broken glass? Yes or No?’

There was no broken glass in the film itself. The results suggested that the word ‘SMASHED’ not only led to estimates of faster speeds but also increased the likelihood of the participants recalling seeing broken glass when none was in the film.

This research suggests that memory is easily distorted by questioning technique and information acquired after the event can merge with original memory causing inaccurate recall or reconstructive memory. The addition of false details to a memory of an event is referred to as conflabulation.

The Loftus & Palmer experiment can be criticised for lacking ecological validity. It employed independent measures design and therefore may be explained by individual differences/subject variables. The controlled conditions make for sound reliability the ethics of this design may be questioned, as the participants were deceived but this was necessary in order to validate findings and minimise demand characteristics. The participants may have been distressed/traumatised by the film and this emotional reaction may have influenced their interpretation of the event.  See Research Methods. This kind of research has led to recommendations concerning police interview techniques and can be used by lawyers in court to question the accuracy of EWT.

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