I Remember It Well...

https://www.youtube.com/watch?v=Z3uMgcRUYBs

"An obvious difficulty which affects allegations and oral evidence based on recollection of events that happened several years ago is the unreliability of human memory." Gestmin SGPS S.A.V Credit Suisse (UK) and others (2013)

Everyone Knows That Human Memory Is Fallible

Yet everyone relies on human memory in order to communicate and socialise. Without recall, social sharing would be severely limited. It is in this context that most people are unaware of the results of over a century of psychological research demonstrating the unreliability of eyewitness testimony. I believe that the legal system has insufficiently absorbed the impact of this research. It operates on the common basis of what most people believe: that the more confident a person is in their recollection, and the more vivid their experience of recall, the more likely it is that their memory of that event is accurate.

Source Memory

A common error is to think that memory is like a snapshot, and the brain a camera. Thus, memory is fixed at the time of the experience and gradually fades over the years or goes to the back of the album. It would seem to follow logically that the more often the 'snapshot' is retrieved, the more vividly it is recalled. However, psychological research has shown counter-intuitively that unlike photographs memories are fluid and malleable. They are being constantly rewritten and modified - like the various drafts of a saved document, or like Wikipedia. You can go in and change the data, but so can everyone else. The previous draft is discarded or modified and the new one retained.

So-called 'flashbulb' memories - those of traumatic or exciting events are, as the term suggests, based on that same false model of the brain as a camera that makes a fixed record of an event. In fact, the brain being an organic entity, forever processing and re-processing data, each time the memory is recovered external date can intrude into the picture and cause dramatic alterations to the memory. Significantly, events can be retrieved as memories which are actually not remembered at all, but which either did not happen or happened to someone else. This phenomenon is referred to in the literature as a failure of source memory. Worryingly, these 'false memories' can be either innocently or maliciously implanted during the therapy process.

Vulnerability of Memory

Changing over time, personal beliefs are imposed and overlaid onto past beliefs to make them more consistent with the present. This can be clearly seen if an individual is presented with new data or insight into an event when the memory is already weak, having faded over time. The person having a particular version of an event, or a party tie of loyalty or set of beliefs (such as commitment to a particular religion or group) will model recall to demonstrate consistency with that allegiance. A desire to create a loyal or faithful impression in a public forum can be a powerful motivation to remember 'correctly'. That is, in accordance with established social/work/group commitments.

So that in a court context, long before the actual trial, memories are regularly refreshed and reconsidered through this pre-trial process of reading case notes, private ruminations and group discussions with lawyers over many months or even years. Often this can include material which did not come into existence until after the event the person is being asked to recall. The final one-off statement in court - the apparent (and often powerful) 'recall' of the original memory, in the presence of a jury, most of whom may believe in the 'photographic' model of memory - will have gone through several iterations before it is actually delivered in the witness box. It may not be the original 'memory' at all. The advice of Mr. justice Leggat is to place little if any reliance at all on witnesses' recollections of what was said [or done] and to base factual findings on inferences drawn from the documentary evidence and known or probable facts...it is important to avoid the fallacy of supposing that, because a witness has confidence in his or her recollection and is honest, evidence based on that recollection provides any reliable guide to the truth.

A Few Simple Observations

('Notes on a lecture' at the Forensic Psychology Unit, Goldsmith's College, London. 18th November 2016)

No gender difference regarding false memory recall has yet been discovered in the research. Even people with very good day to day memory, who can accurately recall events, can be just as susceptible to false memory implantation.

Some people believe that it would be ethical to implant good memories. For example, making someone falsely remember an unpleasant experience with fatty foods could help them to lose weight.

In the current situation it possible for a lay person to do a weekend course in regression therapy and set themselves up to start taking clients.

50% of people remember a paparazzi video of Princess Diana's car crash, when in fact there is no such video.

With current knowledge lie detectors are unable to distinguish false memories from real ones. There is rich emotional content to a false memory and therefore strong physiological arousal when that memory is recalled. The physiological responses - heart rate, breathing rate, blood pressure, which lie detectors measure would be the same for a false memory as for a real one.

False memories can lead to wrong convictions. For example three-quarters of 300 prisoners exonerated by DNA evidence in the US were wrongly convicted by false eyewitness testimony.