An eyewitness is a person present at an event who has seen or can give first hand evidence of the event. In this case, he is a person who testifies in a court of law to events or facts within his own knowledge.
In giving his testimony, an eyewitness while disclosing facts within his knowledge or recounting an event the way he had witnessed it may be sincere but sincerely wrong. This means while he may be speaking the truth from his own perspective, he may be grossly erroneous and misrepresenting facts. A vivid example is that of a milkman who appears in court to say that he saw Mr Jones throw off his wife’s mother from the third story bedroom when in reality, Mr Jones’ mother-in-law could have fallen out of the window and Mr Jones was trying to catch her before falling. Perspective is everything.
The human memory is very crucial to accurate testimony by an eyewitness. While the eyewitness is supposed to recall and represent whole and wholesome truth to the court it should be noted that he is not a pre-programmed machine and as such might not be able to recall everything as it happened.
The human memory goes through three stages: acquisition of information, storage and retrieval of the information. Errors may creep into the eyewitness testimony at any stage of the memory. Neuroscience studies indicate that memory is a reconstructive process that is susceptible to distortion. This distortion could however result from several factors.
The emotional arousal of the eyewitness is one factor which could lead to an erroneous recount. Witnesses with certain emotional tendencies tend to edit their account of events wherein such emotions are aroused. Experimental evidence shows that emotional arousal can lead to poor recall for details. A witness easily aroused at the sight of blood will most likely doctor his account of an event to suit his emotions.
Cultural variation could be another error inducing factor in eyewitness testimony. The race or culture of the eyewitness or the person about whom the recall is being made could affect the accuracy of the testimony. For example, the Chinese to an average Nigerian all look the same, so recalling the face of a Chinese rapist by a Nigerian victim could be a Herculean task and inevitably lead to error in recounting such ordeal or even identifying the culprit in a line-up of Chinese men. This is because of lack of experience and familiarity in meeting people of different groups.
Third parties could also introduce false facts into memory. Lending credence to this error are experiments carried out by Elizabeth Loftus in the mid-seventies where people were shown the slide of a car at an intersection with either a yield sign or a stop sign. Experimenters asked participants questions, falsely introducing the term “stop sign” into the question instead of referring to the yield sign participants had actually seen. Similarly, experimenters falsely substituted the term “yield sign” in questions directed to participants who had actually seen the stop sign slide. The results indicated that subjects remembered seeing the false image. The introduction of false cues could alter eyewitness testimony.
Gap filling and assumptions also affect memory. Human beings constantly fill in the gaps in recollecting and interpreting the things they hear. For example, a student might hear “examination”, “twenty-sixth”, “biology” while passing by the staff room. Building on this assumptions and knowledge, he might report having heard that examinations are to start on the twenty-sixth with biology as the first subject.
Eyewitnesses can also distort their own memory while retelling without the help of police officers, examiners or lawyers. Since eyewitnesses tell and retell to different people for different purposes, they deliberately, sometimes on impulse doctor the story and tailor their account to their audience even without any suggestion from a third party. For instance, an eyewitness will most likely keep back incriminating parts of his testimony from a police officer while revealing such to his lawyer. So, the personality of the person being addressed could make an eyewitness distort facts or keep back or reveal certain parts of his testimony.
Realizing the importance of eyewitness testimony in the judicial process and the weight given to personal testimony, it is important to also take into cognizance, the fallibility of eyewitnesses. Different worldviews through which interpretations are made, emotions, stress, bias, authority figures like police officers, lawyers or even the age of the witness are other likely error inducing factors that could influence eyewitness testimony. In the courtroom, even minor memory distortions can have severe consequence. This is partly driven by common misunderstandings about memory-for example, that memory is more veridical than it may actually be. Therefore, errors in eyewitness testimonies while they may be inevitable must be reduced to the barest minimum by averting the mind of the judge, jury and examiners to likely errors and error inducing factors so that they will know what to expect from and how to relate with eyewitnesses who while being confident and sincere, may be sincerely wrong.