Blind lineup administration as a prophylactic against the postidentification feedback effect.

Area of Science:

• Psychology
• Forensic Science
• Cognitive Psychology

Background:

• Eyewitness testimony is crucial in legal cases.
• Postidentification feedback can distort witness confidence and memory.
• Double-blind procedures are proposed to mitigate feedback effects but lack empirical testing.

Purpose of the Study:

• To investigate the effectiveness of double-blind lineup procedures in preventing postidentification feedback effects.
• To examine the interaction between blind administration and feedback on eyewitness judgments.
• To test the predictions of the selective cue integration framework.

Main Methods:

• Mock witnesses viewed a staged crime and participated in a target-present or target-absent lineup.
• Lineup administrators were either presumed to know the suspect's identity or not (blind condition).
• Participants received nonidentification-specific feedback and then rated their confidence and other judgments.

Main Results:

• A significant interaction was found between blind condition and feedback.
• Feedback inflated confidence and judgments only in presumed nonblind conditions.
• Feedback had no effect on participants in presumed blind conditions.
• The interaction was significant only for inaccurate witnesses.

Conclusions:

• Double-blind administration can serve as a prophylactic measure against the distorting effects of postidentification feedback.
• Even subtle feedback can significantly influence eyewitness judgments.
• Lineup administrators should avoid providing any form of feedback to eyewitnesses to maintain testimony integrity.