eyewitness testimony

what did Loftus + Palmer research

investigated how misleading information could distort eyewitness testimony accounts

what was the procedure in Loftus + Palmer’s research

45 american students as participants

a lab experiment

participants were shown slides of a car accident and then asked to describe what had happened.

they were asked specific questions such as

“how fast were the cars going when they (hit/smashed/collided/bumped/contacted) each other?’

what were the findings of Loftus + Palmers research

the estimated speed given by participants was affected by the wording of the question

participants asked with ‘smash’ predicted higher speeds than ‘contacted’

evaluate Loftus + Palmer’s study

• lacks mundane realism

• lacks ecological validity

• students are not representative

• demand characteristics

• followed a standardised procedure so easy to replicate

what factors affect the accuracy of eyewitness testimony

• misleading information

• leading questions

• post-event discussion

• anxiety

Loftus + Palmer and post-event discussion

• found 17% participants recalled seeing a barn a week after watching a video of a car ride, when asked ‘how fast was the car going when it passed the white barn’ when there was no barn

• shows post-even discussion added to the memory after the event had occurred

anxiety + accuracy of recall

Yerkes-Dodson effect

when anxiety levels are low and high, EWT is less accurate then when it is at medium level

what did Loftus et al find about weapons, anxiety and recall

found that if a person carries a weapon, the witness focuses on the weapon more than anything else

they then have poor accurate recall on other factors such as details of the person holding the weapon…

how can you improve the accuracy of EWT

the cognitive interview

what are the 4 parts to the cognitive interview

• change of narrative order

• change of perspective

• mental reinstatement of context

• recalling all information, even which seem irrelevant

what are the main 3 additional features of the cognitive interview

• encourages the witness to relax and speak slowly, reducing anxiety

• offer comments to help clarify witness statements, open questions

• adapt questions to suit the understanding of the individual witness

evaluate the cognitive interview

• more time consuming than standard police interview

• some elements of the interview are more valuable than others

• sometimes incorrect things are recalled

• police have to be trained, expensive and time consuming