Eyewitness misidentification is the single greatest cause of wrongful convictions nationwide, playing a role in nearly 75% of convictions overturned through DNA testing.
Some bad identifications can start from the very beginning based on simple factors, such as: the lighting when the crime took place or the distance from which the witness saw the perpetrator. Other variables also include more complex factors, including race (identifications have proven to be less accurate when witnesses are identifying perpetrators of a different race), the presence of a weapon during a crime and the degree of stress or trauma a witness experienced while seeing the perpetrator.
To compound these problems the police in show-ups, line-ups may have communicated and implied to the witness who they think suspect criminal is. The police may have used suggestive line-ups, where in an extreme circumstance where the suspect is African-American and he is put into a line-up with five white guys.
The following are factors that are part of the Florida jury instructions regarding witness identification:
The capacity and opportunity of the eyewitness to observe the offender based upon the length of time for observation and the conditions at the time of observation, including lighting and distance.
Whether the identification was the product of the eyewitness’s own recollection or was the result of influence or suggestiveness.
The circumstances under which the defendant was presented to the eyewitness for identification.
Any inconsistent identifications made by the eyewitness.
Any instance in which the eyewitness did not make an identification when given the opportunity to do so.
The witness’s familiarity with the subject identified.
Lapses of time between the event and the identification[s].
Whether the eyewitness and the offender are of different races or ethnic groups, and whether this may have affected the accuracy of the identification.
The totality of circumstances surrounding the eyewitness’s identification.