Improving the Accuracy of Eyewitnesses in the Presence of Misinformation with the Plurality Option


Karlos Luna, School of Psychology, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.



Misinformation has negative effects in the accuracy of eyewitnesses' reports. We investigated whether those negative effects could be reduced when participants are allowed to decide how many answers to include in their answers, that is, to regulate the plurality option. Participants watched a slideshow and received misinformation through a narrative. In the recognition memory test, participants had to select, out of five alternatives, one (single) and then three alternatives (plural answer) and to indicate which one they preferred to report if they were in a courtroom. Perceived likelihood ratings were also collected. Results showed that the regulation of the plurality option increased accuracy even in the presence of misinformation and highlighted the importance of the perceived likelihood ratings in the decision to select a single or plural answer. In general, the results suggest that better testimonies could be obtained if witnesses are given some control over their answers. Copyright © 2012 John Wiley & Sons, Ltd.