Case File 269 · Investigation Psychology

Can Repeated Recall Improve Memory?

By Murder Book Editorial TeamPublished by Gungrounds, the studio making Murder BookPublished 3 October 2026Updated 3 October 2026

Repeated recall can improve memory, but it can also introduce complications. A landmark 1988 study by Scrivner and Safer found that eyewitnesses who recalled a violent event across four successive trials remembered significantly more correct details with each attempt, rising from 38% of details on the first trial to 61% across all four. These gains came with only a minimal increase in errors. However, later research has shown that repeated testing can also increase susceptibility to misleading information encountered between recall attempts. The answer, then, is nuanced: repeated recall tends to strengthen retention of genuine memories, but it does not make memory immune to distortion.

Key takeaways

Eyewitnesses who recall an event multiple times often remember additional correct details on later attempts, a phenomenon researchers call reminiscence.
In one study, witnesses recalled 38% of details on a first attempt but reported 61% across four trials, with minimal new errors.
The testing effect, well established in cognitive psychology, shows that retrieving information strengthens long-term retention more than simply restudying it.
Repeated recall can also increase vulnerability to misleading post-event information, a finding called retrieval-enhanced suggestibility.
New details that appear in later recall attempts are not automatically less accurate than details reported first.

What happens when witnesses recall an event more than once?

It is common for investigators to interview a witness more than once. A widespread assumption is that a witness tells everything they know on the first attempt and that anything added later is suspect. Research challenges this assumption.

Scrivner and Safer (1988) had participants watch a two-minute videotape of a violent burglary and then recall details across four trials, including one 48 hours later. With each trial, participants reported previously unmentioned details from every segment of the tape. The gains were not the result of increased guessing: accuracy remained high throughout. The researchers concluded that single-trial studies may seriously underestimate what a witness can report.

This pattern, in which repeated recall produces new correct details without a proportional rise in errors, is sometimes called reminiscence. A related term, hypermnesia, refers to an overall net improvement in recall across trials. Erdelyi (1996) reviewed decades of research on hypermnesia and concluded that the effect is robust across many types of material, though it is more reliably found with pictorial or emotional content. For more on how memory works differently from a recording, the distinction matters: new details on a second or third attempt do not necessarily mean the witness is fabricating.

What is the testing effect?

The benefits of repeated recall are closely related to a broader finding in cognitive psychology known as the testing effect. Roediger and Karpicke (2006), in a study published in Psychological Science, demonstrated that students who practised retrieving information from a passage retained 61% of it after one week, compared with 40% for students who spent the same time rereading. The act of retrieval itself strengthened the memory trace.

This finding has been replicated hundreds of times across different materials and settings. A 2011 study by Roediger and Butler, published in Trends in Cognitive Sciences, reviewed the evidence and confirmed that retrieval practice is one of the most effective ways to promote durable learning. The mechanism appears to involve strengthening the retrieval pathways themselves, so that each successful recall makes the next one easier.

For eyewitness memory specifically, the implication is that an early recall attempt, even an informal one, may help preserve details that would otherwise fade. This is one reason the cognitive interview technique encourages witnesses to provide a full free recall as soon as possible after an event.

Can repeated recall also cause problems?

Yes. Research by Chan, Thomas and Bulevich (2009) identified a phenomenon they called retrieval-enhanced suggestibility. In their experiments, participants who took an initial test about a witnessed event were more likely than untested participants to incorporate misleading information they encountered afterwards. The initial test appeared to make memory more open to revision, not just more durable.

This creates a tension. Repeated recall strengthens what is already stored, but it may also make the witness more receptive to post-event information, including inaccurate details from news reports, conversations with other witnesses, or leading questions from interviewers. The practical lesson is that the conditions surrounding each recall attempt matter. If a witness is exposed to misleading information between interviews, repeated recall might lock in the distortion rather than correct it.

Later research found that warning participants about the possibility of misleading information eliminated the retrieval-enhanced suggestibility effect. This suggests that careful interview protocols, including reminding witnesses to report only what they personally observed, can reduce the risk.

Do later details deserve less trust?

Not automatically. The assumption that first reports are best and later additions are less reliable is sometimes called the primacy of first accounts belief. Scrivner and Safer's data directly contradicts this: many details reported for the first time on a second, third or fourth trial were accurate.

However, later additions do require careful evaluation. An investigator needs to consider whether the witness has been exposed to new information between interviews, whether the new detail is consistent with the existing evidence, and whether the witness can explain why they did not mention it earlier. Why truthful accounts can be inconsistent explores why honest recall naturally shifts between attempts.

A reasonable approach is to treat each recall attempt as one more sample of what the witness remembers, rather than assuming the first attempt captured everything and anything new is unreliable.

What about repeated questioning by investigators?

There is an important difference between a witness freely recalling an event multiple times and an investigator asking the same question repeatedly within a single interview. Repeated questioning within one session can signal to the witness that their first answer was wrong, prompting them to change it. Research on repeated questioning and memory has found that children in particular are susceptible to changing their answers when a question is asked again, interpreting the repetition as pressure to give a different response.

The testing effect research supports giving witnesses multiple opportunities to recall, ideally separated by time. It does not support pressing a witness on the same point within a single interview as a way to get a better answer.

How does Murder Book handle repeated accounts?

Murder Book: The Art of Interrogation is an upcoming narrative interrogation game from Gungrounds, an independent studio in Zagreb, Croatia. Players examine unreliable stories, behavioural changes and contradictions across a suspect's account. Development screenshots show a branching case map and a casebook tracking behaviours such as Fabrication, Avoidance and Narrative Gaps. The game challenges players to notice what changes between tellings and decide whether a shift signals new honesty, recovered memory, or something else entirely. Since behaviour is not proof, the game asks players to weigh uncertainty rather than reach a simple verdict.

Murder Book is in development for PC (Steam) and mobile, with release currently planned for the end of Q2 2027.