See also: CREDIBILITY; EXPERTS; IDENTIFICATIONS; SCIENTIFIC EVIDENCE

The reliability of eyewitness testimony has been the subject of much debate in scientific literature as well as in the courts.  Eyewitness testimony has been shown to be subject to a number of psychological factors, including: diminishing memory; stress; the incorporation of inaccurate information gathered after the event; "unconscious transfer" resulting in an incorrect identification in a line-up; the unreliability of cross-racial identification; and the effect of lighting, distance, and duration.{footnote}United States v. Downing, 753 F.2d 1224 (3d Cir. 1985).{/footnote}  When the prosecution relies on an eyewitness identification of the defendant as the perpetrator in a criminal case, some courts have held that the defendant may offer qualified expert testimony on specific psychological factors that could have affected the accuracy of the identification.{footnote}United States v. Mathis, 264 F.3d 321, 342 (3d Cir. 2001) (exclusion was abuse of discretion); United States v. Downing, 753 F.2d 1224 (3d Cir. 1985) (expert testimony concerning the unreliability of eyewitnesses should be allowed when meeting standard of Fed. R. Evid. 702); United States v. Moore, 786 F.2d 1308 (5th Cir. 1986) (such testimony, though properly excluded in case at bar, may be necessary to a proper defense where critical to the prosecution’s case); United States v. Smithers, 212 F.3d 306, 311, 314, 318 (6th Cir. 2000) (exclusion was abuse of discretion);United States v. Smith, 736 F.2d 1103, 1107 (6th Cir. 1984) (though finding improper exclusion of expert testimony harmless error); United States v. Beck, 393 F.3d 1088, 1092 n.2 (9th Cir. 2005); United States v. Sullivan, 246 F. Supp. 2d 696, 697, 700 (E.D. Ky. 2003).
Skamarocius v. State, 731 P.2d 63, 67 (Alaska Ct. App. 1987); State v. Chapple, 660 P.2d 1208, 1224 (Ariz. 1983) (expert testimony regarding unreliability of eyewitness should have been admitted where eyewitnesses identified defendant in a photo lineup over one year after the event occurred); People v. McDonald, 37 Cal. 3d 351, 690 P.2d 709, 208 Cal. Rptr. 236 (1984); State v. DuBray, 317 Mont. 377, 77 P.3d 247 (2003); State v. Taylor, 749 P.2d 181 (Wash. App. Ct. 1988); State v. Moon, 726 P.2d 1263 (Wash. App. Ct. 1986).
Contra United States v. Serna, 799 F.2d 842, 850 (2d Cir. 1986), cert. denied, 481 U.S. 1013 (1987) (excluding expert testimony where expert "acknowledged that many of his conclusions coincided with common sense."); United States v. Fischer, 587 F.2d 365 (7th Cir. 1978), cert. denied, 439 U.S. 1132 (1979) (work in the field of ethnic eyewitness identification still inadequate, thus it does not qualify as specialized knowledge); United States v. Watson, 587 F.2d 365, 369 (7th Cir. 1978) (expert testimony on cross-racial identification insufficiently developed as a science), cert. denied, 439 U.S. 1132 (1979); United States v. Christophe, 833 F.2d 1296 (9th Cir. 1987) (jurors are aware of the problems of eyewitness identification); United States v. Brewer, 783 F.2d 841, 843 (9th Cir.) ("cross-examination should be effective to expose any inconsistencies or deficiencies in eyewitness identification."), cert. denied, 463 U.S. 831 (1986).
See also United States v. Lester, 254 F. Supp. 2d 602, 612–13 (E.D. Va. 2003) (granting in part and denying in part eyewitness expert testimony).
See also People v. Nix, 479 N.E.2d 1147, 1151 (Ill. App. Ct. 1985) (expert testimony that stress affected the ability of the victim to perceive the details of an assault properly excluded as credibility of witnesses is strictly within the competence of the fact finder); Commonwealth v. Francis, 453 N.E.2d 1204 (Mass. 1983) (safeguards such as cross-examination, closing argument, and regular jury instructions generally provide adequate protection); State v. Wooden, 658 S.W.2d 553, 557 (Tenn. Crim. App. 1983).{/footnote}  One court has approved a special identification instruction for use in cases when eyewitnesses testify.{footnote}United States v. Telfaire, 469 F.2d 552 (D.C. Cir. 1972).{/footnote}

Bibliography

Greer, Anything But the Truth?  The Reliability of Testimony in Criminal Trials, 11 Brit. J. Criminology 131, 133-35 (1971).
Loftus & Schneider, Behold With Strange Surprise: Judicial Reactions To Expert Testimony Concerning Eyewitness Reliability, 56 U.M.K.C. L. Rev. 1 (1987).
Sanders, Expert Witnesses in Eyewitness Facial Identification Cases, 17 Tex. Tech L. Rev. 1409, 1439 (1986).
The Daubert Trilogy in the States, 44 Jurimetrics J. 351 n. 17 (Spring 2004)
Overbeck, Beyond Admissibility: A Practical Look At The Use Of Eyewitness Expert Testimony In The Federal Courts, 15 N.Y.U. L. Rev. 1895 (2005).