Eyewitness Testimony - Misleading Information

Eyewitness testimony is a legal term. It refers to an account given by people of an event they have witnessed. 

For example they may be required to give a description at a trial of a robbery or a road accident someone has seen.  This includes identification of perpetrators, details of the crime scene etc.

Juries tend to pay close attention to eyewitness testimony and generally find it a reliable source of information.  However, research into this area has found that eyewitness testimony can be affected by many psychological factors.

One of these factors is Misleading Information.

A leading question is a question that suggests what answer is desired or leads to the desired answer.

In the case of the Loftus and Palmer Study the leading questions are created by using verbs with different intensities such as smashed and hit.

Aim: To test their hypothesis that the language used in eyewitness testimony can alter memory.

They aimed to show that leading questions could distort eyewitness testimony accounts and so have a negative effect, as the account would become distorted by cues provided in the question.

To test this Loftus and Palmer (1974) asked people to estimate the speed of motor vehicles using different forms of questions. Estimating vehicle speed is something people are generally poor at and so they may be more open to suggestion.

Procedure: 45 American students formed an opportunity sample. This was a laboratory experiment with five conditions, only one of which was experienced by each participant (an independent measures experimental design).

7 films of traffic accidents, ranging in duration from 5 to 30 seconds, were presented in a random order to each group. After watching the film participants were asked to describe what had happened as if they were eyewitnesses. They were then asked specific questions, including the question “About how fast were the cars going when they (smashed / collided / bumped / hit / contacted) each other?” The IV was the verb in the question and the DV was the speed reported by the participants.

Findings: The estimated speed was affected by the verb used. The verb implied information about the speed, which systematically affected the participants’ memory of the accident.

• Participants who were asked the “smashed” question thought the cars were going faster than those who were asked the “hit” question. The participants in the “smashed” condition reported the highest speed estimate (40.8 mph), followed by “collided” (39.3 mph), “bumped” (38.1 mph), “hit” (34 mph), and “contacted” (31.8 mph) in descending order.

Conclusion: The results show that the verb conveyed an impression of the speed the car was travelling and this altered the participants' perceptions. In other words, eyewitness testimony might be biased by the way questions are asked after a crime is committed.There are two explanations:

• Response-bias factors: The misleading information provided may have simply influenced the answer a person gave but didn't actually lead to a false memory of the event. 
• The memory representation is altered: The critical verb changes a person's perception of the accident - some critical words would lead someone to have a perception of the accident being more serious.

• One limitation of the research is that it lacked mundane realism / ecological validity. Participants viewed video clips rather than being present at a real life accident.

• A study conducted by Yuille and Cutshall (1986) conflicts the findings of this study. They found that misleading information did not alter the memory of people who had witnessed a real armed robbery. This implies that misleading information may have a greater influence in the lab rather and that Loftus and Palmer's study may have lacked ecological validity.

• A further problem with the study was the use of students as participants. Students are not representative of the general population in a number of ways. Importantly they may be less experienced drivers and therefore less confident in their ability to estimate speeds. This may have influenced them to be more swayed by the verb in the question.

• A strength of the study is it's easy to replicate (i.e. copy). This is because the method was a laboratory experiment which followed a standardised procedure.