The effect of surgical masks on identification decisions from masked and unmasked lineups

AbstractWhile research has shown that wearing a disguise hinders lineup identifications, less is known about how to conduct lineups in cases of disguised perpetrators. We examined the influence of surgical masks, worn during a crime event (encoding) and within lineups (retrieval), on eyewitness identification accuracy. In our experiment, 452 participants watched a mock-crime video and identified the perpetrator from either a target-present or a target-absent simultaneous lineup. Contrary to expectations based on the encoding specificity principle, we did not find that matching the presence of masks in the lineup to the encoding condition increased identification accuracy. Instead, compared to the condition with no masks at encoding and retrieval, the presence of masks at either stage negatively affected discriminability and undermined the predictive utility of confidence and decision time. Our findings indicate that when a witness has encountered a masked perpetrator, presenting them with a masked lineup may not be necessary.Keywords: disguiseencoding specificity principleeyewitnessface recognitionidentification accuracylineupssurgical masks AcknowledgementsWe wish to thank Erlend Art Arras for help with creating the photo and video stimuli, Maris Soonsein and Marjaliisa Palu for editing the photo stimuli, Ats Veske and Christofer Robert Mäeumbaed for help with data collection and Kirke Kaur for help with the theoretical overview.Ethical standardsDeclaration of conflicts of interestAnnegrete Palu has declared no conflicts of interest.Aire Raidvee has declared no conflicts of interest.Valeri Murnikov has declared no conflicts of interest.Kristjan Kask has declared no conflicts of interest.Ethical approvalAll procedures performed in studies involving human participants were in accordance with the ethical standards of the Research Ethics Committee of the University of Tartu and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.Informed consentInformed consent was obtained from all individual participants included in the studySupplemental dataSupplemental material is available via the ‘Supplementary’ tab on the article’s online page (https://dx.doi.org/10.1080/13218719.2023.2242435).Data availability statementThe data that support the findings of this study are available from the corresponding author upon request.Additional informationFundingThis research was partially supported by the Estonian Research Council [grant number PRG1151].