Cognitive Processes of Eyewitness Testimonies

PS200 FINAL DRAFT-UNIT 5

Kaplan University

The human memory is a fragile component, many different aspects account for how we perceive, store, and later recall memories; raising question to the reliability of eyewitness testimonies, as they are often the primary or only source of evidence when investigating and convicting a crime. Eyewitness testimonies typically consist of an oral account of what one individual has witnessed. Reviewing the cognitive processes from the time information is received to the time it is retrieved is critical in understanding the possible errors which may affect the accuracy of eyewitness accounts. Jurors are inclined to believe a confident eyewitness, and being so, is it just to convict a defendant based on eyewitness testimonies?

Information processing begins with the cognitive process of perception. This is where stimulus is recognized, allowing us to make sense of the world around us; while attention, gives the mind the ability to concentrate mental efforts on specific stimuli. These processes are complex cognitive functions constantly evolving with each new item passing through. Perception and attention rely on both: top-down processing, access to information already stored in memory and Bottom-up processing, the unique characteristics of given stimuli, this combination allows us to make inferences to decrease the amount of specific information needing processed and stored.

Memory is a broad-stroke term which encompasses the many processes by which the mind retains information. Beginning with our working (or short-term) memory, tasked with holding a limited amount of information currently being processed, and ending with our long-term memory. Long-term memory is often subdivided for convenience based on the type of information stored. Semantic memory is our memory of general knowledge about the world. It is the explicit storage and retrieval of cultural facts, ideals and meanings. Episodic memory, contains information about events that have happened to us personally; allowing an individual to consciously travel back in time to reminisce about earlier periods of their life. (Matlin & Farmer, 2016). Procedural memory, stores memories formed through repeating complex task over and over again, until retrieval takes no conscious effort; it is the storage of all our implicit daily processes. Eyewitness testimonies rely on autobiographical memory, a combination of semantic and episodic memory. Often these events are traumatic and emotionally arousing creating a “flashbulb memory.”

Many of the general population believe flashbulb memories are more accurate than memories of ordinary events, however, the encoding (representation in memory) and retrieval (access to information) processes are just the same as ordinary memories (Lacy & Starck, 2013). The level at which information is processed during encoding, known as the depth-of-processing approach, theorizes that deep, meaningful processing of information leads to more accurate recall. However, with this approach memories are often guided by schemas to be categorized with others of similar content or meaning. Even when information was elaborated, the recall of a memory now categorized can have missing information allowing the possibility of inferences, spontaneous generalization, or default assignments to fill in the blanks (Matlin & Farmer, 2016).

Comparatively, the encoding-specificity principle states recall is more accurate if the context during retrieval is similar to the context during encoding, giving valid reason to the situated cognition approach which theorizes the use of environmental information when encoding events or situations. The shallow processing suggested by this approach can be more accurate when recalling superficial information (Matlin & Farmer, 2016).

Another theoretical approach, connectionism, suggest our knowledge of individuals might be stored by connections linking similar characteristics with one another (Matlin & Farmer, 2016). As such, an eyewitness’ accuracy at recalling the identity of a suspect of another ethnicity is relatively low considering a phenomenon called cross-ethnicity effect. Where accuracy decreases with identifying members of another ethnic group, typically because people interact more often with members of their own ethnic group, therefore gaining expertise on typical features. Conversely, the self-reference effect has shown improved recall when information can be related to one’s self, meaning identifying a suspect of the same ethnic group could be easier with thoughts like, “He had the same nose as my dad!” However, the typicality effect of judging typical items (characteristics typical of your ethnic group) faster than those that are not typical could also hinder an eyewitness’s accuracy at identify a suspect.

Furthermore, other factors such as post-event misinformation, where misleading information learned after the event may be incorporated into recall, or false memories where knowledge and schemas create memories of events that never took place, and even consistency-bias, a tendency to recall information to align with our current beliefs and viewpoints may also alter an eyewitness’ memory. That said, the accuracy of memories typically declines the greater the amount of time from when it was generated, and more so with each recall. Social pressure, interview techniques, and police feedback are frequent topics of eyewitness memory errors as well.

Ideally, Jurors would be aware of the malleability of autobiographical memories and all the potential error and faults. However, that is rarely the case given the widely held belief that the degree of confidence correlates with the degree of accuracy. In fact, research conducted by Leippe and Eisenstadt (2007) shows the correlation between confidence and accuracy are typically between +0.30 and +0.50; +1.00 being the strongest correlation (as cited in Matlin & Farmer, 2016).

In conclusion, with consideration to the fragile nature of human memory, I cannot support or agree with the beliefs that the testimony of one confident eyewitness is enough evidence to convict a defendant of a crime, or that memory accuracy increases with supposed confidence. The use of empirical evidence from research on eyewitness memory, casts a shadow of doubt on the reliability, therefore, I believe it to be unethical for jurors to consider eyewitness testimonies as evidence. Levin & Cramer (1968) said it best, “Eyewitness testimony is, at best, evidence of what the witness believes to have occurred. It may or may not tell what actually happened.”

References

Lacy, J.W. & Starck, C.E.L. (2013). The Neuroscience of Memory: Implications for the Courtroom. Nature Reviews. Neuroscience, 14(9), 649-658. http://doi.org/10.1038/nrn3563

Levin, L. & Cramer, H. (1968). Trial Advocacy Problems and Materials.

New York, New York: Foundation Press.

Matlin, M.W. & Farmer, T.A. (2016). Cognition, 9th Edition [VitalSouce bookshelf version]. Retrieved from https://kaplan.vitalsource.com/#/books/9781119177678/