The Role of Metamemory in Eyewitness Testimony

Estimating eyewitness memory accuracy is crucial in forensic settings, given the need for efficient investigations and the negative consequences of erroneous testimony. In fact, mistaken identifications of innocent suspects have contributed to numerous miscarriages of justice, which often results in many years of innocent lives spent in prison. Eyewitness psychology research has established that eyewitness memory is not a permanent record of perceived events and may be tainted by a number of different factors. Witnesses recollections of important facts not only deteriorate over time but can also be negatively distorted by new information introduced after the original experience. In this thesis, the overarching goal of the research was to test the utility of metamemory assessments as postdictors of eyewitness performance. Metamemory research is essential for a comprehensive understanding of how people use and perceive their own memory, but it has not yet been thoroughly explored in eyewitness settings. Six experiments were conducted, providing new findings that help elucidate the relationship between metamemory and eyewitness accuracy, confidence, and over/underconfidence in forensic settings. More specifically, I investigate how self-ratings of memory ability relate to eyewitness performance in the identification and free recall contexts. These experiments provided initial evidence that some metamemory factors may be important indicators of eyewitness identification accuracy and confidence. It has also been found that eyewitness-specific metamemory factors are predictive of identification accuracy for both biased and unbiased lineups. In this thesis, I summarize the main findings of this novel line of research, presenting the challenges and prospects facing future eyewitness metamemory research.