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Are Eye Witness Testimonies Influenced by Leading Questions?

Candidate Name: Candidate Number: Session: March 2009Subject: Psychology Level: StandardWord Count: 1499Date of submission: 09/03/‘09


Abstract

The aim of this experiment was to conclude whether leading questions influence recall of information. It

was replicated from Palmer and Loftus’ experiment regarding eyewitness testimonies and memory, an

area focused in cognitive psychology. After the participants watched a video of a car accident (the

independent variable) and had a distraction exercise, they were asked the speed of the car which included

leading questions. The leading questions comprised of different words such as ‘hit’ or ‘smashed’, as they

implied different speeds.

After analyzing the results, it can be concluded that the leading questions did influence the results as

participants chose higher speeds whereas the control group chose lower speeds. The dependent variable,

which was the responses to the leading questions, were unexpected to a certain degree but overall, these

results do support Palmer and Loftus’ experiment, the reconstructive theory and Barlett’s theory

regarding schemas which was developed through the distraction exercise.

Although some unexpected results were obtained, this experiment was successful as the first hypothesis

was accepted and a clear conclusion was reached: that eyewitness testimonies are not reliable since

factors such as leading questions can affect recall

Words count: 188


Table of Contents

Introduction 1 Methodology:i. Designii. Participantsiii. Materialsiv. Procedure

33455

Results 7 Discussion 8 References 9 Appendix A 10 Appendix B 11 Appendix C 12 Appendix D 15 Appendix E 16 Appendix F 17


INTRODUCTION

The cognitive perspective examines internal mental processes including perception, language and focuses

greatly on memory. Memory is the ability to acquire and recover stored information later. Atkinson and

Shriffin (1968) proposed a theory suggesting that processing and storage of memory is in 3 different

stages: encode, store and retrieve in a consecutive and discontinuous way.

Everyday uses of visual reports are believed of being reliable, however, researchers are questioning their

reliability implying that eyewitness reports are overrated as they’re based on visual perception which can

be easily distorted. Retrieving information can be influenced by many factors such as race, clothing,

violence, misleading questions, schemas and reconstructive errors can occur often. It can also be affected

depending on context, the state/mood of a person and it usually needs prompting with clues.

Courtrooms depend on eyewitness testimonies when investigating crimes and can have severe

consequences. It is necessary that this area of memory should be investigated to test its accuracy as they

are vulnerable of being distorted after an event. Jurors are unaware of influencing factors and limitations

of memories and usually rely on eyewitness testimonies.

Studies have been carried out to investigate whether eyewitness testimonies should be trusted and has

influenced many theories; Palmer and Loftus’ experiment aimed to investigate how information given

after an event can influence memory. Their results support the reconstructive hypothesis which means

that a memory of an event consists of two types of information: one gathered from perceiving an event

and the second is the information that is given after the event, such as leading questions. Both types of

information combine and can then create a memory that differs from what was first perceived.


Palmer, Loftus’ and Barlett’s experiment is based on the reconstructive theory of memory and schemas.

“A schema is, broadly speaking, a set of mental expectations that accompany a situation.”1 Schemas can

form stereotypes, affecting eyewitness testimonies as it causes distortions in memories as existing

schemas conflict with new information. Schemas influence our memory and helps by filling in the gaps

when we have incomplete memories as we make “inferences or deductions about what could or should

have happened.”2 Fiske and Taylor (1991) verified that confusion can occur when a leading question may

be asked in an eyewitness testimony due to our schemas and stereotyped beliefs stored in our semantic

memory which is based on meaning.

To see whether information supplied to us, after an event can influence memory, we replicated Palmer

and Loftus’ experiment. Using leading questions, our experiment aimed to see if language affects and

influence recall and ultimately memory. The experiment carried out has plenty of scope for extending it

and repeating similar experiments will result in the most accurate results and ecological validity which

will help to conclude whether the reconstructive theory and leading questions have an influence on

memory. .

The hypotheses formed are:

H0 : Leading questions will not influence recall-there will be no difference between the control and

experimental groups.

H1 : Leading questions will influence recall.

Word count: 501

1 http://uk.geocities.com/selvrtanni/articles/eyewitness.htm2 Richard Gross, Psychology The Science of Mind and Behaviour, 4th Edition, 2005, pg. 312


METHODOLOGYi.) Design:

An independent measures design was used because each group, consisting of different participants,

received a different questionnaire. The different participants resulted in no order effects, which is an

advantage of this design. Although a disadvantage is that errors could be made due to the individual

differences in the different groups.

To ensure that we were not crossing ethical boundaries, the participants signed consent forms3, they were

debriefed4 before and after the experiment, they had the right to withdraw from the experiment and they

were not harmed in any way, physically or emotionally (even the video of the car accident was not

severe).

The independent variables in this experiment were the different leading questions and the visual stimulus:

the video of the road accident. The dependent variable was the responses to the leading questions. The

controlled variables were the standardized instructions5, the video was shown only once to all groups, a

distraction exercise was given for 5 minutes to all groups (to allow for fading of memory trace)6, silence

was requested throughout the video and participants were seated at a distance from each other.

A single blind experiment7 was conducted so no participant biases occurred and the experiment was

conducted only once so that no order effects or participant biases could occur. The same experimenters

read out the standardized instructions and gave the debriefing so that participants were familiar with their

accent and voice (which minimized errors).

3 See Appendix A pg. 104 See Appendix B pg. 115 See Appendix B pg. 116 See Appendix B pg. 117 (i.e. the participants do not know whether they are in the control group or they are part of an experimental group)


ii.) Participants:

20 students (both genders) were used. The target population was grade 12 students from Emirates

International School. The mean age of the students was 16 years and 10 months. The 20 students were

split up into 3 groups.

Convenience sampling was used it was the most convenient and it the results are usually accurate for the

targeted population which can be considered as a strength. The nationalities of the students varied due to

an international school which can raise cultural biases in the experiment and is a limitation of

convenience sampling.

iii.) Materials:

Video of a road accident8

Questionnaires9

iv.) Procedure:

The participants were debriefed10 and given standardized instructions.11

A video12 of a road accident was shown

They were divided into 3 groups

For 5 minutes, the groups had individual distracting questions13 involving car accidents.

8 See Appendix D pg. 159 See Appendix C pg. 11-1410 See Appendix B pg. 1111 See Appendix B pg. 1112 See Appendix D pg. 1513 See Appendix B pg. 11


They were given questionnaires14 to fill in.

After 5 minutes, the questionnaires were then collected.

The participants were thanked and debriefed15 again.

Results were collated and statistically analyzed.

Word count of methodology: 407

14 See Appendix C pg. 12-1415 See Appendix B pg. 11


RESULTS 16 Table Illustrating the Statement of Results from the Experiment Including the Mean and Standard

DeviationControl Group A Experimental Group

BExperimental Group

C

Mean 110 km 120 km 123.33

Standard Deviation

19.2 22.4 5.7

Group C had the highest mean speed and group A had the lowest mean speed. Group B has the second

highest mean speed. The aim of this experiment was to see whether leading questions have an influence

on memory and whether eyewitness testimonies are reliable. There is a correlation between leading

questions and memories; control group A has the lowest mean speed whereas experimental group B and

C-which includes the leading questions-have higher mean speeds. It can be briefly stated that our

experiment has been successful since the results match our main expectations.

Bar Graph Illustrating the Mean Speed Results of Each Group from the Experiment

16 See Appendix E pg. 16


DISCUSSION

As per the results, the null hypothesis (H0) is rejected and the first hypothesis (H1) is accepted because the

leading questions including the words “smash” and “hit” led to an increase in the number of participants

who chose a higher speed. The control group had the lowest average speed compared to the experimental

groups but unexpectedly, experimental group C had a higher mean speed than experimental group B. We

expected group B’s average speed to be higher than group C’s because the word “smashed” implies a

greater strength compared to “hit” and Palmer’s and Loftus’ experiment had a greater average speed

when the word smash was used rather than hit.

The unexpected results can explain that the appropriate leading questions are necessary to formulate the

desired response. It could be possible that the words “smashed” and “hit” were interpreted differently due

to the different nationalities and English may not have been the participants’ first language.

Limitations that restricted the accuracy of the results obtained include the small number of participants

that were used due to the lack of participants available which is a weakness of convenience sampling as 1

group had an unequal number of students. Improvements such as a larger group with less individual

differences like nationalities could have been made.

A response-bias factor17 could have occurred or perhaps the leading questions changed the participant’s

view of the accident. The participant might have recalled the accident as being more severe than it

17 meaning that if the participant was unsure what speed to choose, the word “smash” or “hit” biases his choice towards the higher speed


actually was due to the leading questions.18 The leading questions and the schema, that were present in the

participant’s memories that may have developed through the distraction exercises, could have also

influenced their responses which supports Barlett’s schema theory.

Lawyers use leading questions with suspects to gain the correct response needed raising ethical

considerations as lawyers can manipulate suspects to win cases. Dr. Gary Wells19 issued the national

guidelines concerning eyewitness testimonies: "like trace evidence, eyewitness evidence can be

contaminated, lost, destroyed or otherwise made to produce results that can lead to an incorrect

reconstruction of the crime,”20 and says that “Loftus's model suggests that crime investigators need to

think about eyewitness evidence in the same way that they think about trace evidence.”21 For example,

the case of J.J. White22-an innocent man who was accused of rape and imprisoned for 27 years due to an

incorrect eyewitness testimony.

In conclusion, although the results obtained were slightly unexpected due to the diverse nationalities and

their own interpretation of the two words, it is clear that the use of any leading questions does have an

effect on recalling an event which supports Palmer and Loftus and Barlett’s experiments. This questions

the eyewitness testimonies produced in courtrooms as they have a large importance on producing a

verdict and has severe consequences. It is important that this issue should be considered as information

obtained from eyewitness testimonies should not be completely relied on as the memory can be

influenced easily by language and leading questions and by other factors.

18 https://webfiles.uci.edu/eloftus/LoftusPalmer74.pdf19 Dr. Gary Wells is an experimental social psychologist and a member of the U.S. Department of Justice panel.20 http://www.apa.org/monitor/apr06/eyewitness.html21 http://www.apa.org/monitor/apr06/eyewitness.html22http://blogs.news.com.au/news/splat/index.php/news/comments/innocent_man_freed_on_dna_evidence_after_27_years/ See Appendix F pg. 17


Discussion word count: 499


References

Webliography: (all last accessed on 8th March 2009)

http://blogs.news.com.au/news/splat/index.php/news/comments/

innocent_man_freed_on_dna_evidence_after_27_years/

http://uk.geocities.com/selvrtanni/articles/eyewitness.htm

http://www.apa.org/monitor/apr06/eyewitness.html

http://www.youtube.com/watch?v=a2DS3RENDY0

https://webfiles.uci.edu/eloftus/LoftusPalmer74.pdf

Bibliography:

Hugh Coolican, Introduction to Research Methods and Statistics in

PSYCHOLOGY, 2nd Edition, Hodder & Stoughton, 2004

Phillip Banyard and Andrew Grayson, Introducing Psychology Research,

Second Edition: Revised and Expanded, Palgrave Macmillan, 2000

Richard Gross, Psychology The Science of Mind and Behaviour, 4th

Edition, 2005


Appendix A

PARTICIPANT INFORMED CONSENT

I have been informed about the nature of the research.

I understand that I have the right to withdraw from the research at any time, and that nay information/data about me will retain confidential.

My anonymity will be protected as my name will not be identifiable.

The research will be conducted so that I will not be demeaned in any way.

I will be debriefed at the end, and have the opportunity to find out the results at a later date.

I give my informed consent to participating in this research.

Name:

Date:

Contact Number:


Appendix B

Standardized Instructions

Thank you for participating in this experiment. We request you to be silent and not talk to the person next to you. Please do not open the question paper which is faced down in front of you. Please have a look at this video. (the video of the car accident is shown)

Distraction Exercises

(after the video) All those with the letter A written at the back of your question paper, please join Experimenter A who is holding a card with the letter A on it. All those with the letter B written at the back of your question paper, please join Experimenter B who is holding a card with the letter B on it. All those with the letter C written at the back of your question paper, please join Experimenter C who is holding a card with the letter C on it. Experimenters A, B and C will have group discussions. Control Group A will talk about traffic on a local highway. Experimental group B will talk about how speed thrills but kills. And experimental group C will talk about whether safe driving can ever be safe. The distraction exercises not only distract the participants but also create a schema in their mind about car accidents, speed and safety.

(after 5 minutes of the distraction exercise) Thank you. Now can you please fill out the questionnaire which is faced down in front of you.

(after the questionnaires have been filled) Thank you for participating in this experiment. Your responses will remain confidential and will be used for research purposes only. We will be happy to tell you the results if you would like to know. Thank you


Appendix C

Questionnaire for Control Group A

Please answer the following questions:-

1. What is your nationality? _________________________

2. Please circle your gender:-

Male Female

3. How old are you? _________________________

4. Do you think speeding on roads while driving is dangerous?

5. What was the colour of the car?

_________________________

6. Going back to the video clip that we showed you- How fast do you think the car was moving when the accident took place?

90 km 120 km 130 km 150 km

7. Did you see the driver in the car? Yes No

8. Do you want a driving license?

Yes No

9. Which car would you like to drive?

_________________________

10. How would you describe you mood in one word?

_________________________


Appendix CQuestionnaire for Experimental Group B




Male Female

3. How old are you? _________________________



_________________________

6. Going back to the video clip that we showed you- How fast do you think the car was moving, when it smashed into the lorry?

90 km 120 km 130 km 150 km



Yes No


_________________________


_________________________


Appendix CQuestionnaire for Experimental Group C




Male Female

3. How old are you? _________________________



_________________________

6. Going back to the video clip that we showed you- How fast do you think the car was moving, when it hit the lorry?

90 km 120 km 130 km 150 km



Yes No


_________________________


_________________________


Appendix D

The video of the road accident was from this website:

http://www.youtube.com/watch?v=a2DS3RENDY0


Appendix ETable Illustrating the Raw Results Obtained From the Experiments

Control Group A Experimental Group B

Experimental Group C

130 km 90 km 120 km

90 km 90 km 120 km120 km 130 km 120 km

90 km 120 km 120 km

90 km 130 km 130 km

130 km 130 km 130 km

120 km 150 kmTotal 770 km 840 km 740 km


Appendix F

innocent man freed on DNA evidence after 27 yearsWHOLE ARTICLE TAKEN FROM: http://blogs.news.com.au/news/splat/index.php/news/comments/innocent_man_freed_on_dna_evidence_after_27_years/

Here’s the curious thing about eye-witness evidence in a court of law: on the one hand it is the most convincing evidence that a jury can hear while, on the other, it is the most unreliable evidence that can be tabled in court.

There was a psychological study done to check just how visually aware members of the public are on any given Sunday… or maybe it was a Monday. A man stopped a passer-by in the street and asked for directions to a nearby street that required a series of at least four instructions (straight, left, right, right again). As the person gave the instructions to the lost passer-by two workers walked between them carrying a double-door. Hanging from the double-door was another man and, out of sight for a moment, he jumped down onto the street while the person who has initially requested directions jumped on and disappeared. Once the double-doors has passed by less than half of the people giving instructions noticed that they were now directing a different person, wearing completely different clothes.

Research has also shown that a person conducting a line-up can influence the witness, by asking leading questions, and encourage them to identify any particular person in the line-up.

And yet time and again we see that nothing convicines a jury so much as a man or a woman standing in court, pointing the finger at the accused and saying, “I saw that man shoot the victim.” Would that our senses could be so reliable in real life.

There’s a story today about J. J. White, a 48 year-old American man who has just been released from jail after being found guilty of rape 27 years ago. DNA evidence has proved that the eye-witness evidence that put him away for life was not accurate. Mr White was released in 1990 after ten years in jail but was sent back to prison in 1997 for arm robbery.

“I was raised on the chain gang,” Mr White said, “and I didn’t know how to make my way once I got out.”

I don’t doubt that for a minute. I’m surprised Mr White survived the resentment that must have threatened to destroy him over those ten years in jail.

Surely these kinds of cases are compelling arguments for the abolition of the death penalty, or should Western democracies still be killing people for killing people? (Mr White was accused of rape, but the eye-witness evidence could easily have been for murder).

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