Yarmey (2004)

Yarmey (2004)

1. Aims

   • look at the effects on both males and females of being part of a field experiment related to eyewitness recall and photo identification
   • see how far a disguise (sunglasses and a baseball cap) affected retrieval
   • The study also used a four-hour time gap and investigated the effect of this gap on eyewitness recall

2. Procedure

   • There were 215 and 375 female participants, ranging in age from 18 to 70
     • Only white participants were used to avoid any race bias
   • Participants were randomly assigned to one of many different conditions:
     • being prepared about being a witness or not
     • a disguise present or not
     • retrieval instructions enhanced or not
     • tested immediately or delayed for four hours
     • the gender of the witness (male or female)
     • whether the target was present or not in a line-up
   • Two white women were the targets
   • Participants were approved by a target in a public place and asked to help look for lost jewellery or asked for directions
   • After two minutes, a female researcher went up to the participant and asked him or her to take part in the study. The researcher either asked then and there about the identification or four hours later.
     • Witnesses were given a questionnaire with 16 items, eight about the physical characteristics of the target and eight about her clothing. They rated their confidence of answer on a 7-point scale.
       • After completing the questionnaire witnesses were given a set of six photos- In half the cases, the target was present
   • At the end of the study there was a debriefing
   • Another part of the study was to give the whole scenario in writing to students. They were asked to comment on what they thought would happen and what would affect eyewitness recall.

3. Results

   • In many cases significant differences were found between the various conditions
   • When the target was present in the photo line-up, about 49% of participants correctly identified the target, and 62% correctly said that the target was not there in the 'Target Absent' condition
     • When 62% correctly said the target was not in the photos, students thought this would happen for only 47% of participants
     • When 49% correctly identified the target was in the line-up, 63% of the students thought that in that condition the target would be correctly identified
   • Another finding was that the participants who were prepared for the test were better at recall but were not better at photo identification
   • With regard to physical characteristics, this study found that age estimates were reasonably accurate

4. Conclusions

   • This study found that about 50% if the time a witness makes a correct identification in a line-up when the target is present, which corresponds closely with the findings of Haber and Haber's meta analysis (2001)
   • It also has practical application. Jurors likely to have similar assumptions to the students