When a witness takes the stand and claims that he or she saw the crime happen and can identify the perpetrator, juries tend to take it seriously. However, there are many factors that can greatly affect a person's perceptions and memories of an event, even when the witness intends to tell the truth.
Experienced defense attorneys may counter the impact of eyewitness testimony by exploring the ways the witness's knowledge of events could have been distorted. It is important for the jury to understand that memories are rarely as reliable as people think. In a criminal case, inaccuracies can seriously affect the course of the case - and the defendant's life.
Here are four things that can compromise the quality of eyewitness testimony.
One of the most common factors that can distort perceptions and memories is extreme stress. In many cases, eyewitness testimony comes from the victims of the crime. A person who is being robbed, assaulted or threatened with a weapon is typically in a lot of distress. Under these circumstances, some perceptions are heightened while others are muted. If the perpetrator has a weapon, most victims will focus more on it than on the assailant's face. Bystanders close enough to observe the crime also tend to experience a high level of stress at the time.
2. Racial differences
Racial differences are another potential barrier to correct identification. Generally, people have greater difficulty telling apart the facial features of persons of another racial group than those of their own group. Thus, if the witness and the accused are of different races, confusion becomes even likelier.
3. Unusual details
If the perpetrator had any kind of unusual characteristic, chances are that the witness focused on it while ignoring other traits. This can lead to confusion, as it is highly unlikely that the person who committed the crime is actually the only person with this unusual height or particular hair color. If the perpetrator wore a disguise, identification can be even harder.
4. Police procedures
Some police procedures can also make it harder for witnesses to remember correctly. Rushed identification procedures can pressure uncertain witnesses to make an identification they are not actually sure of. Once witnesses make an identification, however, it is human nature to double down and claim they are more confident in their opinion than they actually are. As a result, the initially hesitant witness can end up on the stand stating that he or she is absolutely confident of the identification.
Despite popular perception, eyewitness testimony is frequently inaccurate and should not be allowed to determine the outcome of the case. A knowledgeable attorney can evaluate the available evidence and develop an optimally effective strategy.