Line-up member similarity influences the effectiveness of a salient rejection option for eyewitnesses

Visually salient line-up rejection options have not been systematically studied with adult eyewitnesses. We explored the impact of using a non-verbal, salient rejection option on adults' identification accuracy for line-ups containing low- or high-similarity fillers. The non-verbal, salient rejection option had minimal impact on accuracy in low-similarity line-ups, but in high-similarity line-ups its inclusion increased correct rejections for target-absent line-ups as well as incorrect rejections in target-present line-ups, relative to a verbal rejection condition. The improved performance in target-absent line-ups suggests that adults, like children, may experience pressure to choose and guess during difficult tasks. This pressure is reduced when a prominent non-verbal rejection option is displayed in the line-up. However, the salient rejection option also appears to increase the attractiveness of avoiding a difficult choice between the target and highly similar fillers. Implications of these findings for the experimental literature and justice system are discussed.