Blind sequential lineup administration reduces both false identifications and confidence in those false...

Area of Science:

• Psychology
• Forensic Science
• Criminal Justice

Background:

• Eyewitness experts widely recommend double-blind lineups, where administrators are unaware of the suspect's identity.
• Empirical research on the impact of nonblind administration on false identifications and witness confidence remains limited and conflicting.

Purpose of the Study:

• To investigate the effect of nonblind versus blind lineup administration on false identifications and witness confidence.
• To explore administrator behaviors that may influence identification outcomes.

Main Methods:

• 312 student participants were assigned roles as lineup administrators or mock witnesses.
• Administrators were randomly assigned to blind or nonblind conditions and presented sequential lineups (target-present or target-absent) to witnesses.
• Administrator interactions were surreptitiously videorecorded.

Main Results:

• Nonblind administration significantly increased false identifications but not correct identifications.
• Witness confidence was significantly inflated for false identifications made under nonblind conditions.
• Nonblind administrators exhibited more smiling behavior during suspect viewing and after identification compared to blind administrators.

Conclusions:

• The findings provide robust support for the use of blind lineup administration.
• Nonblind administration can inflate false identifications and confidence, highlighting the need for standardized blind procedures.
• Administrator behavior, such as smiling, may inadvertently influence eyewitness decisions.