The Relation of Output Order and Commission Errors in Free Recall and Eyewitness Accounts

We explored the relation between output order and the likelihood of a commission error in free recall under both laboratory and eyewitness conditions. In Experiment 1, participants studied a list of 20 unrelated words and, after a five-minute distractor task, were asked to recall those words. Whereas the items that participants recalled were mostly correct, commission errors were more likely to occur at the end of a participant's output. In Experiment 2, participants viewed a police film depicting an armed robbery. Participants described the perpetrators, their truck, and the sequence of events during the robbery. When describing the perpetrators or the truck, commission errors were more likely to occur at the end of the output. However, when describing the sequence of events, commission errors were more likely to occur in the middle of the output. In Experiment 3, we replicated the finding that commission errors are likely to occur at the end of the output order when participants are describing people. We speculate on the potential application of this finding and its theoretical underpinnings.