Eyewitness Memory Distortion Following Co-Witness Discussion: A Replication of Garry, French, Kinzett, and Mori (2008) in Ten Countries

Abstract

Please refer to published version for the most recent bibliographic citation information. If a published version is known of, the repository item page linked to above, will contain details on accessing it.

Reinforced self‐affirmation as a method for reducing eyewitness memory conformity: An experimental examination using a modified MORI technique

“…We will examine the co‐witness suggestibility effect following the procedure of Garry et al (2008, also, Ito et al, 2019). Like Garry et al, we will analyse the final test accuracy scores for the critical questions using analysis of variance (ANOVA).…”

“…As for the replication of the memory conformity effect, the expected effect size of 1.92 (Hedges g ) can be based on existing results for a Polish sample in research in which the same procedure was used as that planned in the proposed study (Ito et al, 2019). This is a very large effect size, and the sample size required for 80% power at alpha level = 0.05 when comparing two independent samples is about N = 12.…”

“…All materials relating to the MORI technique are available on the OSF page . Importantly, the MORI technique has already been successfully translated into Polish (Ito et al, 2019).…”

“…Several studies using the MORI technique have successfully provided solid evidence for the co‐witness suggestibility effect (French, Garry, & Mori, 2008, 2011; Garry et al, 2008; Kanematsu et al, 1996/2003; Mori & Kitabayashi, 2009; Mori & Mori, 2008; Mori & Takahashi, 2012; Tainaka, Miyoshi, & Mori, 2014). Importantly, this effect seems to be robust and common to many cultures (e.g., Ito et al, 2019). In general, the findings demonstrated that people more often provide correct answers to questions about details not discussed with a co‐witness than to details that were discussed.…”

“…Thus, it may be argued that one plausible source of false eyewitness testimony might be the phenomenon known as memory conformity ; namely, the fact that co‐witnesses integrate elements of each other's version of events into their own report of the shared experience (Wright, Self, & Justice, 2000). Indeed, many studies have shown that such discussion may easily distort people's memory (e.g., Garry, French, Kinzett, & Mori, 2008; Kanematsu, Mori, & Mori, 1996/2003; see Condon, Ritchie, & Igou, 2015; Ito et al, 2019, for a comprehensive review).…”