EYEWITNESS TESTIMONY

Eyewitness Testimony

Eyewitness Testimony

Introduction

Eyewitness Testimony is principally a legal expression for the use of an eyewitness to a crime who testifies in court about the personality of the individual who has been charged with a crime (Plotnik & Kouyoumjian, 2011). The word is common in forensic psychology and has a large literature dealing with the trustworthiness of eyewitnesses and the weight of their testimony. A number of mental and psychological studies have showed that eyewitness testimony has a high propensity for inaccuracy (Davies, 1996). This paper aims to discuss why eyewitness testimony should not be used in the criminal justice system.

Discussion

Issues at every phase of the memory process - retrieval, retention and acquisition - can shape the accuracy of an eyewitness identification or account. First, during the acquisition stage, factors that relate to the circumstances and nature of the event may influence the resulting information as much as the characteristics of the witness (Dwyer, 2001). For instance, with regard to the circumstances of the event, it is reasonable to consider that factors such as lighting conditions, distance, and obstructed view do play a crucial role. Likewise, the duration of the event and the amount of time spent actually observing the event may also affect accuracy; the longer a person looks at something the better the memory of it will be and vice versa (Coon et al., 2010).

However, some estimates - particularly of how long certain events lasted - are frequently inaccurate regardless of the surrounding circumstances of the observation. The nature of the event may also impact the accuracy of memory. Events perceived as insignificant at the time of acquisition are less likely to be recalled accurately. In addition, some research suggests that acts of violence are particularly difficult to recall accurately (Nevid, 2009). Witnesses also often face difficulties when trying to recall events that occurred immediately prior to their observations of violent actions. Research has also shown that highly attractive and unattractive faces are more accurately recognized than others (Haber, 1998).

The type of witnesses can also have an effect on accuracy of recollection. For instance, the psychological condition of the witness can be a significant determiner. Research has demonstrated that fear and stress improve physical performance and, up to a certain point, eyewitness performance; although it becomes counterproductive (known as the Yerkes-Dodson law). In addition, people who experience general chronic levels of stress or stress associated with life changes (e.g., death of a spouse, job change) show reduced memory performance, presumably because the stress causes preoccupation and distraction. And of course, the physical condition of the observer, such as intoxication or eyesight, may also significantly affect accuracy.

A witness' expectations may also affect the ultimate accuracy of statements, i.e. the way one tends to recall certain events is often the way they expect them to occur. Interestingly, in one study, subjects were asked to estimate a person's weight after being told some information about that person. Subjects' estimates of the person's weight were less when subjects were told that the ...