Lineup and showup identifications are admissible as non-hearsay statements under Rule 801(d)(1)(C) of the Federal Rules of Evidence as long as the identifying witness testifies at trial. The evidence of a trial witness' prior identification may be presented by a third party who was present at the identifications, see United States v. Elemy, 656 F.2d 507 (9th Cir. 1981), but the percipient witness must testify at trial. See United States v. Owens, 484 U.S. 554 (1988) (effect of failure of memory).
Updated December 18, 2015