Shift & Stick

Two experiments were conducted to see if asking witnesses to take another look at the lineup after they voiced their identification decisions would alter their choices, and if confirming feedback could then be used to solidify the selections they shifted to. Participants watched a simulated crime and were asked to identify the culprit from a photographic lineup. After voicing their identification decisions, participants were prompted to reexamine the lineup. Half of the participants then received confirming feedback for their decisions, regardless of whether they shifted to a new picture or not. Later on, a different experimenter escorted participants to a second room and administered the same lineup again. In Experiment 1 (N = 432), biased instructions were used to encourage choosing, and when participants were prompted to reexamine the lineup, 70% changed their identification decisions and selected a different picture. When that new selection was reinforced with feedback and participants were given a second opportunity to identify the culprit at a later time, 72% selected the picture they shifted to as the culprit. Participants who made their decisions more quickly were less likely to shift, but accuracy did not predict shifting. This general pattern of findings was replicated using unbiased instructions in Experiment 2 (N = 237). Results suggest that prompting witnesses to reexamine the lineup can often lead witnesses to change their identification decisions, and when the altered choice is reinforced, they will often stay with that influenced decision over time, asserting it with a high degree of confidence.

This is the latest study we have published using our 'Shift & Stick' Paradigm. The shift and stick paradigm involves two basic elements:1) Shift: After voicing their initial identification decision, but before documenting the final choice, participants are told, “Take another look, does anyone [else] look familiar?” . This prompt consistently leads a large majority of participant/witnesses to shift their identification decisions and selected a different picture. 2) Stick: After shifting, witnesses are given confirming feedback to reinforce the shifted selection, and after some delay they are administered the same lineup again. When given a second chance to identify the culprit, most of those witnesses who shifted to another picture and then had that altered decision reinforced with confirming feedback go on to select the same picture they had shifted to. In the current experiment, we examined how variations in encoding conditions could influence witnesses vulnerability to this sort of suggestive behavior by the lineup administrator