Officers should not provide feedback, encouragement, or reinforcement to eyewitnesses before, during, or after an identification procedure.
a. Avoiding suggestion. An overarching goal of these Principles is to avoid suggestion so that an eyewitness’s memory is assessed in a reliable manner. Suggestion in the form of feedback or reinforcement from officers can powerfully affect an eyewitness. Consistently applied, clear and neutral verbal instructions can help to prevent any such feedback. If officers depart from that script and make additional encouraging or confirming remarks, the memory of the eyewitness can be affected or even altered. It can be quite understandable and natural for an officer to desire to congratulate or support an eyewitness who is able to make an identification. That is why it is important that policies forcefully bar any such feedback or reinforcement.
b. Preventing reinforcement or feedback. Blind or blinded procedures can minimize the opportunity for suggestive comments, feedback, or reinforcement to occur, before, after, or during an eyewitness identification, as discussed in § 10.05. Policy and training should reflect the need to minimize interaction with an eyewitness, and particularly the type of encouraging remarks or conduct that might contaminate the eyewitness identification by providing feedback.
c. Trial preparation. Following an eyewitness identification, the eyewitness then may have additional conversations with officers and with prosecutors. In particular, as part of the preparation for hearings or a trial, the eyewitness may be given information about the defendant. That information can powerfully affect the eyewitness’s confidence that the correct identification was made. Officers and lawyers should encourage cooperation and participation of witnesses without disclosing information that might affect the memory of a witness. However, because such information may be communicated, the effect of such interactions on memory makes it all the more important that a careful confidence statement be taken at the time of the initial eyewitness identification procedure.
Eyewitness memory is highly malleable. Suggestion can powerfully affect the reliability of an eyewitness, and suggestion can occur before, during, and after an eyewitness identification procedure. Scientific research has shown that the accuracy and confidence of an eyewitness can be affected by feedback or reinforcement provided by officers before, during, or after the procedure. See, e.g., Nancy K. Steblay et al., Sequential Lineup Laps and Eyewitness Accuracy, 35 Law & Hum. Behav. 262, 271 (2011); A. B. Douglass & Nancy K. Steblay, Memory Distortion in Eyewitnesses: A Meta-Analysis of the Post-Identification Feedback Effect, 20 Applied Cognitive Psychol. 859-869 (2006); Gary L. Wells et al., Eyewitness Identification Procedures: Recommendations for Lineups and Photospreads, 22 Law & Hum. Behav. 603, 630-631 (1998).
Blind or blinded procedures seek to eliminate the possibility of reinforcement or feedback during an eyewitness identification procedure, because the officer does not know which person is the suspect and cannot provide any cues even inadvertently; that is the purpose of such procedures. However, blind procedures, together with an accurate record of an eyewitness identification procedure, will not necessarily prevent suggestion in the form of reinforcement or feedback that occurred before or after that procedure. For example, if an eyewitness is told that the culprit has been arrested and is present in a photo array, even if the eyewitness identification procedure is videotaped, the suggestion already will have occurred and may affect the eyewitness’s memory and decisionmaking. Similarly, if an eyewitness is congratulated on making the correct choice and given other confirming information after the procedure, that eyewitness will be predictably more confident at the time of any hearing or trial. Carl M. Allwood, Jens Knutsson & Pär A. Granhag, Eyewitnesses Under Influence: How Feedback Affects the Realism in Confidence Judgements, 12 Psychol., Crime & L. 25-38 (2006).
This Section recognizes that as part of trial preparation, officers and prosecutors must discuss many aspects of the case with an eyewitness. That process inevitably will cement the eyewitness’s confidence, including based on the simple fact that a case is going forward based in part on the identification evidence. However, even as part of that preparation process, agencies should, through policy and training, counsel against reinforcement or feedback to the eyewitness.