Administrator blindness affects the recording of eyewitness lineup outcomes

We investigated the effects of administrator knowledge of suspect identity in a lineup (blind vs. nonblind), witness identification (suspect vs. filler), and witness confidence (high vs. low) on whether administrators recorded the identification as an affirmative response; whether administrators recorded qualitative notes regarding the lineup task; and the content of those qualitative notes.

We predicted that nonblind administrators would record more identifications of the suspect than the filler, but blind administrators would record such identifications at comparable rates. We predicted this difference would be larger in the low (vs. high) confidence condition. We examined effects on administrators' qualitative notes in an exploratory fashion.

Undergraduate participant administrators (N = 488) presented a lineup to a confederate witness (who made a scripted identification decision) and completed a record of the lineup task.

Nonblind administrators recorded 25% fewer identifications of fillers (vs. suspects), and evaluated witnesses less favorably in the filler (vs. suspect) identification condition (η_p² = .194). Blind administrators were not influenced by witness selection. Blind (vs. nonblind) administrators recorded more qualitative notes, confidence statements, and information relevant to witnesses' decision processes, regardless of whether witnesses identified the suspect or the filler. Among those who recorded a confidence statement, nonblind administrators' characterizations were biased such that independent coders judged witnesses to be more confident in their identifications of the suspect (vs. filler).

Blind administration eliminates numerous biases associated with administrator expectations and may yield more informative lineup records. These results further support blind lineup reform recommendations. (PsycINFO Database Record (c) 2020 APA, all rights reserved).