Fisher et al., (1989) – The Cognitive Interview

Fisher et al., (1986) – ‘Field test of the cognitive interview: enhancing the recollection of the actual vicitims and witnesses of crime’, Journal of Applied Psychology 74 (5), 722-7.


This study is also referred to as:

  • Fisher et al., (1989)
  • Fisher and Geiselman (1989)
  • Geiselman et al., (1989)


This is the third study we look at from the ‘Interviewing Witnesses’ section of ‘Making a case’. As part of your OCR A2 Psychology Exam. It is further categorised into ‘The Cognitive Interview.

Fisher et al., (1989) focuses on police interviews of witnesses.

What is an interview?

An interview is simply trying to elicit information from a person or witness, while keeping the information valid. This is easier said than done. You may remember two studies from AS: Loftus et al., (1974) and Samuel and Bryant (1984), which demonstrate this.  Firstly, Loftus showed the impact that leading questions could have upon participant recall and she concluded that an actual change in memory had occurred. Memory is easily malleable, changing how a question is asked can change the memory itself. Secondly, Samuel and Bryant showed the impact of repeating the same question. Repeating the same question to children will cause them to completely change their answer, even if their answers were perfectly correct.

One of the most important aspects of police work is the ability it obtain accurate and detailed information from eyewitnesses of crime. One experienced judge has stated that incorrect eyewitness identifications have led to more miscarriages of justice than all other factors combined (Sobel,1972).

Fisher et al, (1986) is an important study to understand. 

This study focuses not at the normal interviews that the police conduct, but something called the enhanced cognitive interview.

“This research evaluated an innovative interview procedure, the cognitive interview, that was designed to aid eyewitnesses recall of the details of crimes.”

– (Fisher et al., 1989)

The enhanced cognitive interview has two underlining assumptions:

  • It is possible to access memories from different retrieval points.
  • Retrieval from memory will be more effective if at the time of retrieval the context of the original event can be reinstated.

There are four main retrieval mnemonics to the cognitive interview:

  1. Interview Similarity — An attempt to reinstate the context of memory, interviews must take account of the external factors. How were the participants feeling emotionally? What was the weather like? “Mentally reinstating the context that surrounded a to-be-remembered event has been shown to be a powerful memory aid in numerous laboratory experiments.” – (Fisher and Geiselman, 1989)
  2. Focused Retrieval — This is also called free recall. Interviewees are encouraged to recall as much as possible without interruptions from the person conducting the interview.
  3. Extensive Retrieval — The interviewer makes as many attempts as possible at retrieval from many entry points, for example: what happened when you entered the building? What happened when you left the building? Irrelevant parts are requested by the interviewer in order to maximise the amount recalled, as the more irrelevant details that the interviewee recalls the more likely they are to remember something significant through association, for example, you might have noticed the something peculiar about the carpet and that led you to recall the criminals shoes.
  4. Witness – Compatible Questioning — Each witness will be different, have different values and perceptions and thus the interviewer should consider that.

To study and test the cognitive interview in the field.


Field experiment with actual interviews of real witnesses by serving Police detectives.


16 detectives from the Robbery Division of Dade County Florida. All were experienced with a minimum of five years with the division.


In the first phase of the experiment, detectives were asked to record a selection of their next interviews using the standard interview techniques they normally used. This took four months and 88 interviews were recorded, mostly relating to bag snatches or robbery. The detectives were then divided into two groups with one being trained on Cognitive Interview techniques.

Training was over four, 60 minute sessions. Seven detectives completed the programme and were used in the results which follow. Over the next seven months more interviews were recorded by the two groups. The post training interviews were analysed by a team at the University of California who were blind to the conditions.


The seven trained detectives elicited 47% more information after training and 63% more information than the untrained detectives. In terms of accuracy, laboratory based research had shown no difference between the cognitive interview and the standard interview with approximately 85% of all statements being correct in all conditions. In this field study, accuracy had to be established by corroboration with another source. In 24 cases with corroborating evidence (16 by pre-trained detectives), 94% of statements were corroborated.

The time taken to interview witnesses using the cognitive interview was longer, but not significantly longer; on average in this study it was one minutes longer.


Strong support was obtained for the effectiveness of the cognitive interview in the field. More information was obtained from witnesses to real events with no loss of accuracy and a minimal increase in time taked to interview them. The results in the field replicated those of the laboratory and perhaps give it more weight although the sample is small and may have been particularly well motiviated to run the trial.

The cognitive interview have since been applied to other clinical settings with therapists using it to develop medical histories.

This study is also referred to as:

  • Fisher et al., (1989)
  • Fisher and Geiselman (1989)
  • Geiselman et al., (1989)
Fisher et al., Evaluation

– Demand characteristics, as Police detectives were paid $50 for participating, they may have feel the need to act in a way which the experimenter would want.

+ Ecological Validity, as the experiment used real police detectives, we can say that the experiment is high in ecological validity.

+ Ethics, as the participants were informed about the interview beforehand, we can say that the study was ethical, however we can argue the opposite as the participants were paid for their participation, which is against the BPS’s code of ethics.

– Ethnocentrism, the study was only focused on detectives from Dade county Florida.

+ Experimenter bias, as the results of both experiments were analysed by laboratory assistants who were blind to the conditions, we can say that the study is lacking in experimenter bias, which is a strength.

+ Construct Validity, the results of the study showed support for the effectiveness of the cognitive interview.


Audio Podcast


Fisher et al., (1986) – ‘Field test of the cognitive interview: enhancing the recollection of the actual vicitims and witnesses of crime’, Journal of Applied Psychology 74 (5), 722-7.


Further Reading

OCR A2 Psychology Student Unit Guide: Unit G543: Forensic Psychology (Student Unit Guides)


Article Name
Fisher et al., (1989) - The Cognitive Interview
Fisher et al., (1989) was a field test of the cognitive interview; a revolutionary technique for interviewing suspects. From the OCR A2 Forensic Psychology Spec