I’m taking a detour in my reading at present into the world of memory. There is a considerable amount of literature out there in relation to police investigations, but not so much for workplace investigations.
One book that I’ve found particularly user-friendly is Daniel Reisberg’s The science of perception and memory: a pragmatic guide for the justice system. (The link is not to Amazon, but to Better World Books, which is a “greener” option when buying books).
The book has made me pause and think about the need for investigators to have a checklist to assess the potential for memory error in witness testimony. If such a checklist would exist, it would contain the following:
- Whether neutral questions were asked by the interviewer. What may surprise you, is that asking questions such as “what were you paying attention to during this event?” will actually increase memory error.
- The extent of the witness’ spontaneity in providing their memories. The less questions we ask as investigators, the less we will potentially contanimate their memories.
- The extent that the event was clearly observed (e.g. viewing angle, amount of light, the complexity of the situation, the amount of attention that was being paid).
- Contamination (otherwise known as source confusion): our memories may have been influuenced after talking to others about the event – particularly if it’s someone we trust (“intrusion error”); or we may have filled the “gaps” in our memory, unconciously.
- The urgency in which the witness is asked to recall a memory: the more pressure we put on a witness, the more they will “fill the gaps” with erroneous memories. This has a technical term: imagination inflation.
- Motivation: the drivers behind the witness’ desire for their recollections to be heard (which are not always noble)
- Plausability: whether the recollection is believable or not (think: being abducted by aliens).
- Retentional retrieval: it is harder to recall memories over time, and our memories fade quickly at first; we may also fail to recall a memory, as we’ve not been given the correct “retrieval cues”.
- After the event memory: when someone recalls an event that they didn’t think was significant that time, but they do now. The chances are that they didn’t lay down a complete memory, and therefore unconsciously they will have “filled the gaps” as they sought to retrieve the partial memory.
- Claiming a flash-bulb memory: when a witness claims that the memory is as clear as the day that it occured….it’s not.
- The level of stress that a witness has or did experience: stress has a negative impact on memory.
Lack of consistency in recalling the details of an event, does not mean that a witness is not credible. Research shows that the other elements recalled by witnesses could be accurate. Equally, just because someone seems super-confident in their recollections, it doesn’t mean that their memories are more accurate than someone feeling less confident.
It should also be noted that many of the above (but not number 5) are “honest memory errors”. As such, witnesses should not be berated for their mistakes in accurately recalling an event, as human beings are unable to spot what is a “real memory” and what part of the memory has been contaminated, unconsciously. And witnesses won’t recall every part of an event – they will only recall what was relevant to them at the time.
I should quickly mention that Reisberg makes a disclaimer: that despite the concerns around memory error, memories are often more accurate than they are inaccurate. So, maybe I’m over-thinking the need for a checklist?