(Mock crime and lineup videos courtesy of Gary Wells: http://www.psychology.iastate.edu/FACULTY/gwells/homepage.htm)
Causes of miscarriages of justice: Borchard (1932): 65 wrongful convictions. Most common causes of error: (a) mistaken identity (29, or 45%, of convictions). In only two cases did the defendant resemble the real culprit. (b) over-reliance on circumstantial evidence. (c) perjury by witnesses. (d) self-incriminating confessions. (e) unreliability of “expert” witnesses.
Brandon and Davies (1972): 70 British cases. (a) Mistaken identification. (b) Self-incriminating confessions.
Bedau and Radelet (1987): 350 cases in USA. Four groups of errors - (a) Errors caused by police investigation prior to trial (23% of sample). 49 (14%) of these involved false confessions, mainly due to coercion. (b) Errors caused by prosecution prior to or during trial (50, or 14% of cases). Most common error was suppression of evidence of innocence. (c) Errors caused by prosecution witness: perjury (117 cases) and mistaken identification (56 cases). (d) Miscellaneous - circumstantial evidence (9%), public demand and outrage (20%).
Eyewitness identification: ID parades (lineups) present the suspect amongst innocent “foils” (distractors). Problem: can be unreliable, due to false positives (false identifications) and false negatives (failing to identify the suspect as “present”).
Why are ID parades so unreliable? 1.Unfamiliar face recognition is poor. 2.Physical changes in the suspect between initial encounter and testing. 3. Witness’ misattribution of feelings of familiarity evoked by a suspect’s face. 4. Jurors have misplaced faith in witnesses’ confidence in their own identification accuracy. 5. Difficult to ensure that lineups are fair (unbiased).
Neil vs. Biggers (1972): U.S. Court’s five criteria for evaluating eyewitnesses: 1.Opportunity of the eyewitness to view the offender at the time of the crime. 2.Witness’ degree of attention. 3.Accuracy of the witness’ prior description of the offender. 4.Level of witness’ certainty at the identification procedure. 5.Length of time betwen crime and identification procedure.
Brown, Deffenbacher and Sturgill (1977): Students saw 5 "criminals". 3 days later, picked them from 15 mugshots. 7 days later, picked them from 5 live line-ups. Identification rates in line-up phase: 45% of "criminals" seen both at crime and in mugshots. 18% of individuals NOT seen at crime OR in mugshots (false recognitions). 29% of individuals NOT seen at crime, but seen in mugshots (false recognitions). Exposure to mugshots increased chances of false identification at line-up phase: familiarity but not context.
Wells, Lieppe and Ostrom (1979): Method for assessing inter-item similarity within a lineup. Non-witnesses try to identify suspect solely by witness' verbal description. Should be at chance; line-up effective size is estimated from the number of successful non- witnesses. Assessed the line-up procedure in a real bank robbery case in which a suspect was identified from a 6-person line-up. By chance, 1/6 of non-witnesses should be successful. In practice, 25/41 non-witnesses identified the suspect. Effective size of the line-up = 41/25 = 1.64 - line-up distractors could almost have been omitted!
Wogalter, Marwitz and Leonard (1992): Foils selected on the basis of their similarity to the suspect produce biased lineups (prototype effects). Alternative methods are fairer (e.g., foils based on similarity to suspect and one foil, or where all faces are equally similar to each other).
Wogalter, Malpass and Burger (1993): Studied how U.S. police officers actually produce lineups. Similarity to suspect was main basis for foil selection (which is bad). 94% decided whether a lineup was "fair" on the basis of their own judgement; plus 77% got a second opinion from another officer.
Simultaneous versus Sequential lineups: Simultaneous lineups allow witness to use a relative judgement strategy – i.e., to compare lineup members, decide which is closest to their memories for the criminal, and then infer this is the guilty person. Result in higher rate of false identifications, when the criminal is absent. That's the one! Well, the one most like him, anyway...
Simultaneous versus Sequential lineups: Sequential lineups force witnesses to adopt an absolute judgement strategy - deciding whether or not the person currently being examined is the criminal. Sequential lineups are superior to simultaneous lineups because they reduce false-positive choices (Cutler and Penrod 1988; Lindsay and Wells 1985; Sporer 1993). That's the one!
Steblay, Dysart, Fulero and LIndsay (2001): Meta-analysis comparing sequential and simultaneous lineups. Correct identifications with target-present lineups: simultaneous: 50% sequential: 35% Correct rejections with target-absent lineups: simultaneous: 49% sequential: 72%
Hybrid lineup presentation procedures: U.K.: sequential presentation, but see the lineup twice. U.S.: sequential presentation, seen twice if witness requests it. Steblay, Dietrich, Ryan, Raczynski and James (2011): Consequences for misidentification? Increase in identifications with two viewings compared to one. Witnesses who chose to view the lineup twice made more errors (with both target-present and target-absent lineups) than witnesses who chose to view it once or were required to view it twice. Hybrid procedure increases errors much more than it increases correct identifications.
Accuracy and confidence: Neil vs. Biggers (1972): Witness confidence should be considered in court. Little relationship between confidence and identification accuracy (e.g. Luus and Wells 1994; Sporer, Penrod, Read and Cutler 1995). Bothwell, Deffenbacher and Brigham (1987): confidence-accuracy correlations ranged from 0.08 to 0.42. Wells and Murray (1984): confidence/accuracy r = 0.07.
Accuracy/confidence relationships and effects of post- identification feedback: Wells and Bradfield (1998): Participants tried to identify gunman from target-absent lineup. Group A: confirming feedback. Group B: disconfirming feedback. Group C: no feedback. Feedback distorted subsequent confidence ratings and retrospective reports of how well they had seen the gunman. Memon and Dixon (2005): Similar study. Effects of negative feedback only: affected confidence but not accuracy.
Wells and Bradfield (1999): No post-identification feedback effects if participants thought privately about their certainty before obtaining feedback. Bradfield, Wells and Olson (2002): Confirming feedback inflated retrospective certainty of inaccurate witnesses but not accurate ones. Wells et al (2003): Accessibility hypothesis: no on-line evaluation of performance, so feedback is best guide. Neuschatz et al (2005): Similar effects for young and old participants – supports accessibility hypothesis rather than trace strength explanation. Skagerberg (2007): PIF effects from discussion with other witnesses. Bradfield et al’s results:
Douglass and Steblay (2006): Meta-analysis of research on post-identification feedback – 2,400 participants. Robust effects of confirming feedback on retrospective certainty, quality of view, memory and attention. Less powerful effects of disconfirming feedback.
Conclusions: Eyewitness identification is highly influential with jurors, but a major cause of miscarriages of justice. Eyewitness confidence is highly influential with jurors, but is (a) an unreliable guide to witnesses’ accuracy; (b) susceptible to alteration by post-identification feedback.
Douglass and Steblay (2006): Recommendations for “good” lineups are: 1.Effective use of fillers. 2. Blind administration of lineup (PACE does not ensure this). 3. Warn witness that the culprit may or may not be present (reduces false identifications by 25% - meta-analysis by Steblay 1997). 4. Sequential presentation. 5. Record eyewitness’ assessment of their certainty at the time identification is made. 6. Do not give witnesses feedback about their identification performance. Legal system should reconsider eyewitness evaluation procedures (e.g. advice to juries). Criteria of “confidence”, “attention”and ”view” should not be used if post-identification feedback was provided.