In the last blog, I elucidated factors in the acquisition and storage of memories that can impact their accuracies. In this blog, I intend to discuss factors in memory retrieval that can lead to false memories.
A very well-known incident of mistaken identity is Jennifer Thomson’s identification of Ronald Cotton as her rapist (The Perfect Witness). After giving police a description of her assailant, Thomson was shown mugshots to compare. She took several minutes to pick a suspect, and after identifying Cotton, she said “I think that’s him.” When Cotton was put in a physical lineup, Thomson picked him again. As she continued to pick him, her confidence in her choice grew. What actually happened was that in the physical lineup, she recognized his face from the mugshots, and this replaced her memory of the true rapist. In court, her testimony and confidence in the identification led to Cotton’s conviction. Cotton met the real rapist in prison (Bobby Poole) as Poole was serving time for multiple rapes. Cotton believed that Poole may have been responsible for Thomson’s assault. Cotton managed to get a new trial after the discovery of another woman who was assaulted the same night as Thomson in the same area, and police had reason to believe they were assaulted by the same man. In trial, Poole (Thomson’s rapist) was presented by the defense as a suspect. However, Thomson still confidently identified Cotton as her rapist, and the second victim was less certain, but she also picked Cotton. Due to Thomson encoding Cotton’s face as her rapist during the lineup, she was unable to recognize her true rapist even when he was in front of her. The other woman likely recognized Cotton’s face from the news and was recalling this. Cotton was vindicated when DNA testing proved he was innocent in both assaults. The DNA confirmed that Poole was Thomson’s rapist. This incident serves as a warning about the accuracy of identifications. Many factors can change either a witness’s confidence or accuracy in identification.
Familiarity-induced bias can lead to a mistaken identification in a lineup. This phenomenon is also known as the mere-exposure effect, where people develop a preference for things that are familiar to them (JASONHREHA). In a lineup, a witness may identify a suspect because they have seen their mugshot before. Witnesses recognize faces and pick them, regardless of whether they saw that face in mugshots or in the scene they were a witness to. This was the case when Thomson picked Cotton in the physical lineup. She recognized his face from the photos she viewed at the police station earlier. When she identified him again years later in court, she was remembering her first identification, even when comparing Cotton to her actual rapist, Poole. She simply replaced the memory of her assailant’s face with that of Cotton’s face since she was exposed to it more often. The mere-exposure effect may also be at play when witnesses see the suspect in the police station, on the news, or simply in other places in their daily life. Mistaken identifications due to this phenomenon are more likely to occur when the real suspect is not in the lineup.
The instructions given during a lineup may bias the witness to wrongly identify a suspect. Researchers have conducted experiments where witnesses are assigned to see a lineup that does or does not contain the actual suspect, and researchers give instructions to choose among those in the lineup or they instruct that the witness does not have to make a choice. In lineups where researchers gave the instruction that the witness did not have to make a choice, there were fewer false identifications than lineups where researchers gave the instructions to pick someone in the lineup (APA). This is because the witnesses given the instruction to choose somebody felt pressured to identify the right person, so that even when the suspect was not in the lineup, they would choose somebody in order to fulfill the instructions.
Feedback given to the witness after identification can lead to changes in memory. In one experiment, witnesses were given a lineup that did not contain the actual suspect, meaning any identification would be false. After making the identification, the researcher would inform them that their choice was correct, that it was incorrect, or would give no feedback on their choice (NSF). The type of feedback given greatly impacted the witness’s belief about their memory, such as how good their view of the event was, their ability to make out facial details of the suspect, and the confidence in their decision. This has a large implication on eyewitness testimony in court. Those who are given positive feedback on their identification become more confident in their memory. Juries tend to view confidence in a memory as a key factor of memory accuracy. However, in studies where participants view someone stating an accurate memory and the same person stating a false memory, participants were no better than chance at correctly selecting the false memory as “false”. This indicates that we are unable to tell when memories are real or made up. When juries hear a false memory, they may inaccurately accept it as true evidence since there are not enough cues to distinguish between accurate and inaccurate memories. In actuality, confidence is not an indicator of memory, as seen with Thomson’s confidence in her identification of Cotton. The speed of identification is better associated with accuracy, as accurate memories are recalled quickly. However, juries do not get to see the actual lineup procedure to determine how quickly witnesses make an identification. Also, confidence in memories grows as they continue to be recalled. Therefore, juries have a harder time distinguishing confident false memories from true recollection.
One method of reducing mistaken identification in the lineup is to introduce a “double-blind” procedure for the lineup. Normally, the person administering the lineup knows the identity of the subject. In this case, they may unintentionally communicate information to the witness that can influence their choice. This can be done with body language, asking the suspects to look closer at the lineup, or by confirming the witness’s choice after they make an identification. In a double-blind lineup, the person administering the lineup does not know the identity of the suspect (Psychology). This removes the possibility of influencing the witness to make a specific choice, and therefore reduces mistaken identifications. However, law enforcement currently does not require a double-blind lineup, but they are informed of possible bias in single-blind lineups (where the administrator knows the suspect’s identity and the witness does not). It is important to take this into account when listening to eyewitness testimony. The identification may have been biased due to the single-blind administration of the lineup.
Obviously a lot of factors influence the accuracy of memories. Therefore, it is important to understand the limitations of memory. We make better witnesses and juries when we understand that not all memories are accurate and we look at all the factors leading up to identification in order to analyze a memory’s accuracy level.