BY ANGELA HANSEN
In a study conducted on criminal-investigation processes, experimenters reported that the principal determinant of whether or not a case is solved is the completeness and accuracy of the eyewitness account. (Rand Corporation, 1975) Many eyewitness accounts are known to be unreliable, constructed and incomplete.(Clifford & Hollin, 1983) This study was conducted to measure the accuracy of three methods used by investigators: the "cognitive interview", the hypnosis interview, and the standard police interview. In a preliminary interview using the cognitive procedure, students were instructed in the four memory retrieval mnemonics when asked to recall a situation in the classroom. Students recalled more correct information using this procedure compared to the hypnosis procedure. Also, the cognitive procedure did not lead to incorrect information and lead to greater eyewitness confidence.
The results of the present experiment found that the cognition and hypnosis methods elicited a greater number of correct items than the police(control) interview. Actually, the results revealed that the number of correct items were the same for both hypnosis and cognition. The results of the cognitive interview closely replicate the results of Geiselman et al. (1984) in which both experiments found the cognitive interview to be useful for the enhancement of eyewitness memory performance both under experimental conditions as well as revealing high ecological validity.
REFERENCE
Geiselman, R.E., Fisher, R.P., MacKinnon, D.P., Holland, H.L. (1985). Eyewitness Memory Enhancement in the Police Interview: Cognitive Retrieval Mnemonics versus Hypnosis. Journal of Applied Psychology, 70(2), 401-412.