From Witness to Web Sleuth: Does Citizen Enquiry on Social Media Affect Formal Eyewitness Identification Procedures?

Abstract

Eyewitnesses to crimes may seek the perpetrator on social media prior to participating in a formal identification procedure, but the effect of this citizen enquiry on the accuracy of eyewitness identification is unclear. The current study used a between-participants design to address this question. Participants viewed a crime video, and after a 1–2-day delay were either exposed to social media including the perpetrator, exposed to social media that substituted an innocent suspect for the perpetrator, or not exposed to social media. Seven days after viewing the crime video, all participants made an identification from a video lineup. It was predicted that exposure to social media that did not contain the guilty suspect would reduce the accuracy of subsequent identifications. Analysis revealed no association between social media exposure and lineup response for target present lineups. For target absent lineups, there was a significant association between social media exposure and lineup response, but this was driven by a higher number of correct rejections for participants who saw the guilty suspect on social media. The results suggest that at least in some circumstances, witnesses searching social media do not have a negative effect on formal ID procedures.

The impact of viewing social media images on eyewitness identification.

“…In one study, viewing an innocent suspect on Twitter significantly increased mistaken identifications of the innocent suspect at a subsequent lineup (Kleider-Offutt et al, 2022). In two additional studies, mistaken lineup identifications of innocent suspects also increased after viewing them on social media (25% increase in Elphick et al, 2021; 15% increase in Havard et al, 2023). Although the increases were not significant relative to controls in the latter two studies, the trends are consistent with the expectation that viewing images of an innocent suspect on social media would have the same contaminating effect as viewing mugshots.…”

“…In two experiments, we tested whether the mutual friends feature on social media would be suggestive of a potential suspect and cause even greater memory contamination than mugshot exposure. Based on the existing research on social media identifications (Elphick et al, 2021; Havard et al, 2023; Kleider-Offutt et al, 2022), there is no evidence that social media exposure affects identification decisions any differently than mugshot exposure does. However, social media and mugshot viewings were not directly compared in any of the previously published experiments.…”

“…Perhaps most analogous to social media searches is the mugshot exposure effect, which is when eyewitnesses who have previously viewed a mugshot of an innocent suspect are more likely to mistakenly identify the suspect at a subsequent lineup procedure (Brown et al, 1977; Deffenbacher et al, 2006). Recent research suggests that searching social media can have similar effects (Elphick et al, 2021; Havard et al, 2023; Kleider-Offutt et al, 2022), but the relative risks posed by social media and mugshot images have never been directly compared. In the present research, we report two experiments examining whether a common feature of social media—the mutual friends indicator—has the potential to cause an even greater risk of misidentification for an innocent suspect.…”

Composite communication: how dissemination of facial composites in the media affects police investigations

“…Furthermore, a phenomenon called ‘websleuthing’ has emerged (Yardley et al 2018), which involves citizen detectives conducting elaborate amateur online investigations to help law enforcement solve crimes, for example, through ‘Facebook identifications’ (Brice 2013). On a smaller scale, eyewitnesses to crimes may search social media to see if they can find the perpetrator (Elphick et al 2021; Havard et al 2021). If such a social media search leads them to a person whom they recognise – rightly or wrongly – as the person who committed the crime, exposure to photos of this person is likely to alter the eyewitness's original memory for the perpetrator, as we will explain in further detail later in this chapter.…”