FORENSIC PSYCHOLOGY
Factors That Predict Accuracy of Eyewitness Testimony
How can we then ensure the accuracy of eyewitness evidence for it to be a strong enough basis for conviction?
There are a lot of factors that can predict the witness accuracy.
The distance between the offender and the witness.
In cases of crime, a large distance between the offender and the future eyewitness isn’t going to bode well for an innocent suspect as the subsequent identification would mostly be based on guesswork. However in situations of serious threat if close proximity would later help in identification is also debatable as stress can also influence memory.
The physical position of the witness in relation to the offender.
Even if our knowledge of this is derived from watching how the protagonist always fails to identify the antagonist because the angle wasn’t good enough, it is still right. Different positions can provide different attributes with which a perpetrator can be identified later. But which one identifies the actual perpetrator is not known.
Counterintuitively, the longer the delay between the crime and the statement by the witness, the better was the accuracy of the witness’s description.
The duration of the crime also influences this aspect
A fleeting moment of proximity would most certainly not be favourable. However if the crime lasts for a longer period of time, recollection would be better. Seriously, how likely are the hostages to forget the face of Hans Gruber in Die Hard or our very own Raghavan in Main Hoon Na?
The feelings of threat experienced by the witness
All of the above factors lose some of their power when the threat experienced by the witness is highly intense. It can have an effect when retrieving a memory as biases at that moment could influence the information recalled. This might be one of the reasons why someone rescued from a highly threatening situation fails to remember most of the details. However research also shows that adults tend to remember threatening faces more than non threatening ones. So the threat here can also help predict the accuracy of the witness.
Most of the characteristics by which a suspect is identified are usually the offender’s sex, race, height and age. Now although their descriptions are accurate, they don’t really make a good case when the multiple suspects have similar general characteristics described above as these don’t help in distinguishing the offender from others who are suspects. For example, knowing that the offender is male is not very much used in identifying the particular person in question.
The case of Ronald Cotton is a must read for those interested in understanding how eyewitness identification can go wrong.
can eyewitness testimonies be affected?
Reference
Howitt, D. (2018). Introduction to Forensic and Criminal Psychology Sixth edition.