A lineup is a relatively formalized procedure wherein a suspect, who is generally already in custody, is placed among a group of other persons whose general appearance resembles the suspect. The witness is then asked whether he can identify the perpetrator of the crime. The result is essentially a test of the reliability of the witness’s identification.
United States v. Wade, together with Gilbert v. California, created the Wade-Gilbert Rule. Under this rule, the Supreme court held post-indictment lineups are a critical stage of the criminal prosecution and the defendant is entitled to have their counsel present at critical stages under the Sixth Amendment. If the defendant is denied his right to counsel at post-indictment lineups, then the lineup is inadmissible. Numerous later cases modify and refine the Wade-Gilbert rule, such as Kirby v. Illinois, which held that Wade-Gilbert did not created a right of counsel for pre-indictment lineups and United States v. Ash, which held the Sixth Amendment right to counsel does not apply to post-indictment photo lineups.
[Last updated in June of 2020 by the Wex Definitions Team]