In a groundbreaking research collaboration between Åbo Akademi University and New York University Shanghai, in partnership with Finland's science center Heureka, a new study sheds light on the intricacies of eyewitness identification. The findings emphasize the significant impact of distance, lighting, and facial disguises on a witness's ability to correctly identify individuals they have seen. This research carries essential implications for law enforcement practices and could redefine how witness testimonies are evaluated.

The study involved the participation of over 1,300 individuals ranging from 5 to 90 years old, making it a unique example of citizen science. Researchers explored the effects of three crucial factors: distance, lighting conditions, and facial disguises (such as sunglasses, hoodies, or a combination of both) on eyewitness identification accuracy. Participants were asked to identify individuals they had seen at various distances (5, 12.5, and 20 meters) and under different lighting conditions (daylight and very dim lighting) both with and without facial disguises.

The most significant discovery was the pivotal role distance plays in identification accuracy. The study found that the farther away an individual is, the more challenging it becomes to correctly identify them later. Facial disguises, particularly sunglasses, had a detrimental impact on identification, making it extremely difficult for witnesses to accurately recognize individuals who were wearing sunglasses even when observed from a distance of just 5 meters in daylight.

New York University Shanghai's Assistant Professor of Psychology, Thomas J. Nyman, emphasized the study's findings regarding individuals wearing sunglasses: "Our results show that if a witness sees someone wearing sunglasses from a distance of 20 meters, it is highly unlikely that they would identify the person correctly later on."

Professor Julia Korkman, specializing in forensic psychology at Åbo Akademi University, highlighted the unique aspect of this study, indicating that the large and diverse participant pool makes the results highly reliable and potentially globally applicable.

"These findings provide us with better insights into evaluating the value of eyewitness identifications, taking into account factors such as distance, lighting, and facial disguises," said Korkman, underscoring the study's significance in guiding future practices related to eyewitness testimony in legal proceedings.