Digital Detectives: Websleuthing Reduces Eyewitness Identification Accuracy in Police Lineups

Area of Science:

• Cognitive Psychology
• Forensic Psychology
• Eyewitness Identification

Background:

• Eyewitnesses increasingly use social media to identify suspects before formal procedures.
• The impact of pre-lineup social media searches on identification accuracy remains understudied.

Purpose of the Study:

• To investigate whether viewing a mock social media profile affects eyewitnesses' subsequent lineup identification accuracy.
• To determine if encountering the actual culprit or a lookalike on social media influences identification performance.

Main Methods:

• An online study with 285 participants who watched a mock crime video.
• Participants viewed social media content (culprit, lookalike, or filler task) after a delay.
• Eyewitness identification accuracy was assessed via a photo lineup one week later.

Main Results:

• Participants who viewed a social media profile with a lookalike were less likely to correctly identify the culprit in a Target Present lineup.
• A significant association was found between seeing a lookalike on social media and reduced lineup accuracy.
• No significant association was observed for Target Absent lineups.

Conclusions:

• Pre-lineup social media searches, particularly encountering lookalikes, can significantly impair eyewitness identification accuracy.
• The findings highlight potential risks of self-directed suspect searches on social media for criminal investigations.
• This research suggests a need to consider social media exposure during eyewitness testimony evaluation.