Evaluation of Eyewitness Memory in A Virtual Crime Scene

Abstract

Introduction: Eyewitness memory plays a crucial role in criminal investigation. The present study examined the effect of retention interval on the accuracy of eyewitness memory and the effect of emotional arousal on the memory of plot relevant and plot irrelevant details. Method: A video (Ghosh, 2020) depicting a shooting scene was chosen to be used in this study. In this video, two men try to shoot a shopkeeper and then run away. A total of 16 subjects, 8 females and 8 males, of the age range 18-55 years participated in this study. All of them were shown the same video clip. Two similar questionnaires, containing 12 questions each was prepared. Each questionnaire contained six plot relevant and six plot irrelevant questions. Plot relevant questions are based on the central details of the crime, which revolves around the violent part, that is, gun shooting (e.g. How any guns did the shooters have). Plot irrelevant questions are related to the peripheral details shown in the video (e.g. Identify the object present in the shopkeeper’s table). One questionnaire was administered immediately after watching the video and the second questionnaire was administered after three days. In order to prevent learning effect, the wording of the questions and response options were slightly changed. Result: A significant difference was observed between the scores in immediate and delayed condition. However, no significant difference was observed between the scores of plot relevant and irrelevant questions. The effect of suggestibility was also observed as some participants who gave a correct answer during the first report gave a completely different answer in the second report, when the wording was slightly changed. Conclusion: It was found that the accuracy of eye witness memory is poorer in delayed condition compared to immediate condition. Thus, the study suggests that criminal investigators should take the testimony of eye witnesses as early as possible, any delay could reduce the amount of details recalled.