What you'll learn

• Why eyewitness testimony can be affected by the wording of questions.
• How Loftus and Palmer tested this in two controlled experiments.
• The key results, conclusions, and evaluation points for AO1, AO2, and AO3.
• How this study links to the Memory theme and the Cognitive area in OCR H567.

The basic problem: can witnesses trust their memories?

In everyday life, we often think memory works like a video recording: you see an event, store it, and play it back later. Loftus and Palmer challenged this. They argued that memory is more reconstructive: when you remember something, you rebuild it using the original event plus later information, expectations, and wording.

The overall idea is that a witness sees an event, then later receives information through questions. That later information can influence what they report, especially if the question is leading.

Key concepts before the study

Leading questions

For example, “How fast was the car going when it smashed into the wall?” suggests a more violent collision than “How fast was the car going when it contacted the wall?”

Post-event information

Loftus and Palmer were interested in whether post-event information could alter memory, not just alter the way people describe it.

Background to Loftus and Palmer

Loftus and Palmer’s paper was called “Reconstruction of Automobile Destruction”. Their work sits in the Cognitive area, which studies internal mental processes such as memory, attention, perception, and thinking.

The key real-world issue was legal: if witnesses can be influenced by question wording, then police interviews and courtroom questioning need to be handled very carefully.

Experiment 1: speed estimates

Aim

The aim was to investigate whether the wording of a question would affect participants’ estimates of how fast cars were travelling in film clips of traffic accidents.

Method

• Sample: 45 students from the University of Washington.
• Design: an independent measures design, meaning each participant took part in only one condition of the critical question.
• Independent variable: the verb used in the question: smashed, collided, bumped, hit, or contacted.
• Dependent variable: the participant’s estimated speed in miles per hour.
• Materials: seven short film clips of car accidents.
• Procedure: participants watched the clips, then answered questions. The critical question was: “About how fast were the cars going when they ___ each other?”

Results

Mean speed estimates were:

• Smashed: 40.8 mph
• Collided: 39.3 mph
• Bumped: 38.1 mph
• Hit: 34.0 mph
• Contacted: 31.8 mph

The more forceful the verb, the higher the estimated speed.

Conclusion from Experiment 1

The wording of the question affected speed estimates. Loftus and Palmer suggested two possible explanations:

• Response bias: participants’ memories did not change, but the verb influenced the answer they chose to give.
• Memory reconstruction: the verb actually altered the participant’s memory of the event.

Experiment 2: did memory actually change?

Experiment 2 was designed to test whether the leading question could affect later memory for details that were not present.

Method

• Sample: 150 students.
• Design: independent measures.
• Independent variable: question condition: smashed, hit, or control.
• Dependent variable: whether participants later reported seeing broken glass.
• Procedure: participants watched a film of a multiple-car accident. One group was asked how fast the cars were going when they smashed into each other. Another group was asked the same question with hit. The control group was not asked a speed question. One week later, all participants were asked: “Did you see any broken glass?”
• Important detail: there was no broken glass in the film.

Results

Number who reported seeing broken glass:

• Smashed: 16 yes, 34 no
• Hit: 7 yes, 43 no
• Control: 6 yes, 44 no

Conclusion from Experiment 2

Experiment 2 supports the idea that post-event information can alter memory, not just the wording of a response. The word smashed may have created a stronger mental image of a severe accident, making broken glass seem more likely.

Evaluation: strengths and weaknesses

Scientific control and reliability

The study was highly controlled. Participants watched the same film clips and answered standardised questions, so Loftus and Palmer could isolate the effect of the verb.

This is a strength because the procedure was standardised and easy to replicate. The study also produced quantitative data, such as mean speed estimates, which makes comparisons clear.

Validity issues

The study may have lower ecological validity, meaning it may not reflect real-life eyewitness situations. Watching a film clip in a laboratory is not the same as witnessing a real accident. Real witnesses may experience shock, fear, personal involvement, and a stronger motivation to be accurate.

However, the controlled setting gives the study higher internal validity, because changes in estimates can be linked more confidently to the wording of the question.

Sampling bias and generalisability

The participants were students, so the sample may not represent the wider population. Students may be younger, more used to psychological tasks, and less experienced drivers than older adults.

This limits how confidently we can apply the findings to all eyewitnesses.

Demand characteristics

Participants may have guessed that the verb mattered and adjusted their estimates. This is especially possible because they were students in a psychology-related setting.

Ethics and the BPS Code

The study involved mild deception because participants were not fully told that the wording of questions was the focus. Under the British Psychological Society Code of Ethics and Conduct, researchers should consider informed consent, deception, right to withdraw, protection from harm, confidentiality, and debriefing.

The ethical risk was low because participants watched films rather than real traumatic events. Still, a debrief would be important so participants understood the true aim afterwards.

Links to the Cognitive area and Memory theme

This study is a classic example of the Cognitive area because it investigates an internal mental process: memory. It also uses controlled experiments, supporting the idea that cognition can be studied scientifically.

For the Memory theme, the study shows that memory is active and reconstructive. Eyewitnesses may be sincere but still inaccurate.

Comparison with the paired study: Grant et al. (1998)

The contemporary paired study in the Memory theme is Grant et al. (1998), which investigated context-dependent memory. Grant et al. found that recall was better when the learning and testing environments matched, such as studying and being tested in the same noise condition.

Similarities:

• Both are in the Cognitive area and study memory.
• Both use controlled experimental methods.
• Both use student participants, which raises generalisability issues.
• Both show that memory is influenced by more than the original information.

Differences:

• Loftus and Palmer studied distortion of eyewitness memory through leading questions.
• Grant et al. studied retrieval and whether matching context helps people remember information.
• Loftus and Palmer has strong forensic application, while Grant et al. is more useful for education and revision strategies.
• Loftus and Palmer’s topic is more ethically and socially sensitive because it relates to legal evidence.