Testing two retrieval strategies to enhance eyewitness memory: Category and location clustering recall.

Asking eyewitnesses to provide an initial account using free recall strategies is a crucial procedure used in most investigative interviews (e.g., cognitive interview or Planning and preparation, Engage and explain, Account clarification and challenge, Closure, and Evaluation [PEACE] model), allowing eyewitnesses to recall accurate and detailed information about the crime. Recent studies suggest clustering retrieval strategies like category clustering recall (CCR) can also be effective for obtaining accurate information from eyewitnesses and perhaps more effective than the change-order mnemonic, a witness-compatible questioning, or a free-recall task. This study compared how effective 3 retrieval strategies were (free recall, CCR, and a new retrieval strategy, location clustering recall [LCR]) for obtaining an initial account from eyewitnesses when used as the sole form of retrieval but combined with compatible preliminary instructions, mnemonics, and procedures that constitute best practice. We used a between-subjects experimental design in which 69 participants watched a mock robbery video and were interviewed 48 hr later with either free recall, CCR, or LCR. Participants interviewed with CCR or LCR recalled a higher number of correct details, particularly person-related details. Participants interviewed with LCR also recalled a higher number of environmental details. Report accuracy was high, and similar, for all groups. This study provides further evidence of the ecological validity of CCR as well as initial evidence suggesting LCR might be an effective retrieval strategy as well. These retrieval strategies (CCR and LCR) might be particularly advantageous in situations in which there are multiple crime-scene locations and/or the interviewer is particularly interested in obtaining information concerning environmental and person-related details.