Jurors’ Beliefs about Memory Evidence


Beliefs about memory play an important role in courtroom contexts, particularly in cases that rely heavily on eyewitness testimony. When jurors evaluate a witness’ memory, they draw from their own knowledge about what influences the reliability and accuracy of memory. But do jurors have an accurate understanding of these issues? Previous research has revealed that people hold many misconceptions about how memory works, and what influences memory accuracy. This is problematic given the serious implications that relying on inaccurate beliefs can have in the courtroom – believing whether a memory is accurate can be the difference between a guilty and a not-guilty verdict.

Most previous studies investigating people’s beliefs about memory have done so by asking people closed questions (e.g. multichoice questions) about memory. These closed question methods limit our understanding of how jurors evaluate memory evidence. They do not tell us which beliefs jurors activate and prioritise when evaluating a testimony, and we may be missing other important beliefs that closed questions do not capture.

Here’s what we did.

The current study built on prior research by adopting an open-ended approach to investigate which memory beliefs jurors bring to the courtroom, and also asked which are likely to be the most influential in their evaluations of eyewitness memory. We asked people a series of open questions about what would convince them of the accuracy of a testimony, then asked them to rank their ideas in order of importance. We found the open question format generated different beliefs from those captured by closed question paradigms. There were other important beliefs that closed question research has not typically focused on, and we gained insights into the beliefs that jurors are likely to activate and prioritise in the courtroom.

Here’s what we found.

The most common and importantly ranked beliefs fell into three categories;

  • accuracy/consistency (e.g. the consistency of the testimony across time and compared to other evidence)
  • narrative coherence (how well the story makes sense), and
  • witness behaviour (e.g. the witnesses demeanour and performance in court).

Our findings suggest that juror evaluations of testimony are underpinned by a variety of beliefs about both memory and human behaviour, many of which contradict evidence drawn from cognitive science. We suggested that as well as evaluating memory, jurors are likely to focus heavily on evaluating the person reporting the memory. This highlights further need for researchers to examine how to educate jurors and counter beliefs that may contribute to poor courtroom decision-making. We highlighted several concerns about jurors relying on unreliable cues to aide them in evaluating testimony, and made suggestions for how jurors may be able to benefit most from education. Our findings can aid the development of future juror trainings or interventions.

Our thanks for your support.

We would like to thank everyone who was involved in making this research possible, especially the adults who responded to our surveys.

Ngā Mihi,

The Applied Developmental Psychology Lab Team

Applied Developmental Psychology Lab
School of Psychology
Victoria University of Wellington

Applied-Developmental-Lab@vuw.ac.nz