Photo lineups in theory are a clever way to identify, further solidify, or remove a suspect. The aim is to potentially trigger a memory of some kind in an eyewitness. And based on the subjects in the photo lineup (around five or six) the witness can then use that triggered memory to identify or eliminate the suspects in an “unbiased” fashion. This in a perfect world would result in the right selection or removal of a suspect. Unfortunately, many inconsistencies can occur during this process and should be factored into the likelihood of being accurate. Things like emotions, amount of time since witnessing, and judgement bias based on human memory can all play a part in a fragmented faulty determination of suspicion/guilt potentially leading to a wrongful conviction.
“Researchers have reported that mistaken identifications are the leading cause of wrongful convictions” (APA, 2014). Given the significant examples we have seen and read about over the years in terms of wrongful convictions and mistaken identity/memories during eye-witness testimony, it is an area which seemingly needs some more reliable methods and standards. One factor that plays a role in the ineffectiveness of photo lineups is the nature of human memory. California Innocence Project says that “our memories take in bits and pieces of the information and process the important aspects” (CIP, 2023). Due to the bits and pieces, we store in our memory, crucial information like age, eye color, race, gender, height, hair color, weight, clothes at the time etc. are more likely to then be incorrectly recalled as our brain tries to fill in the blanks of the situation that were not memorized immediately.
Another aspect that plays a role are emotions of the eyewitness. A notable study showed that results “suggest that while emotional participants again provide a more complete description of the perpetrator, they are less able than their neutral counterparts to recognize the perpetrator from a photographic lineup” (Houston et al., 2013). This is important to take into account as it demonstrates that when people have heightened stress and emotions, they may unintentionally alter some aspects of their memory or just are unable to put together everything they did remember in order to rationally select the correct perpetrator.
The last component which results in potential unreliability of photo lineups is the length of time between the eyewitness perpetrator identification and the actual incident that occurred. When looking to get the best identification of an individual as possible “time itself is not a causal factor [for overconfidence], but merely a facilitator of processes that may cause variations in memory and confidence” (Gustafsson et al., 2022). This is important as it highlights the serious potential memory deterioration that can happen naturally due to increasing time after witnessing an incident. And interestingly, despite some eyewitnesses being more confident in their recollection, time was still a major factor in accuracy of recalling memories and identifying a perpetrator. Overall, after having researched the subject deeper, it was very interesting to learn the history of how the photo lineups came to be after the notorious 1-on-1 and police lineups.
References:
American Psychological Association. (2014, April 1). Eyewitness accuracy in police lineups. https://www.apa.org/topics/forensics-law-public-safety/eyewitness-accuracy-police-lineups
Eyewitness identification problems & procedures | CIP. (2023). https://californiainnocenceproject.org/issues-we-face/eyewitness-identification/
Houston, K. A., Clifford, B. R., Phillips, L. H., & Memon, A. (2013). The emotional eyewitness: the effects of emotion on specific aspects of eyewitness recall and recognition performance. Emotion (Washington, D.C.), 13(1), 118–128. https://doi.org/10.1037/a0029220
Gustafsson, P. U., Lindholm, T., & Jönsson, F. U. (2022). Eyewitness accuracy and retrieval effort: Effects of time and repetition. PloS one, 17(9), e0273455. https://doi.org/10.1371/journal.pone.0273455