Problems in Eyewitness Identification


In 2014, the Pennsylvania Supreme Court overturned a per se ban on expert testimony in cases that hinge on eyewitness identification. In a criminal trial, almost no evidence is more damaging to the accused than a complaining witness or eyewitness’s in-court identification – that moment where she takes the stand, in front of a jury, and literally points her finger at the accused. But eyewitness identification is fraught with pitfalls. Recent psychological studies have shown several factors which call into question the identification by an eyewitness. The problem with a case rises and falls on an eyewitness identification is that the victim of a crime is often not intentionally lying, but simply mistaken in her belief. Although the witness is mistaken, the jury attaches a great deal of weight to the eyewitness identification. With this decision, expert testimony now can be used to explain the circumstances and psychological underpinnings of this high, courtroom drama and how the witness may believe sincerely she is telling the truth, but is incorrect in that belief.

In that case – Commonwealth v. Walker – the defendant was convicted of robbery and related charges stemming from an armed robbery in Philadelphia. The trial court precluded the defense from offering expert testimony relating to errors in eye-witness identification. The Pennsylvania Supreme Court overruled the trial court, allowing expert testimony regarding eyewitness identification and its pitfalls for the first time. Recently, the Philadelphia courts took up this issue and ruled that – for the first time in Pennsylvania – an expert can testify about and explain to a jury the psychology behind eyewitness identification.

When confronted with eyewitness identifications, a person accused of a crime can now offer expert testimony regarding the psychology involved in such scenarios. Most eyewitness identifications – or perhaps more appropriately misidentifications – are not malicious. Those scenarios arise where the eyewitness truly believes she picked the correct person but is mistaken in that belief. The expert testimony helps explain how an eyewitness can be incorrect in her sincere belief that she made the proper identification. Although not an exhaustive list, the accused can now offer expert psychological testimony where appropriate in the following areas:

  1. Weapon focus – where a weapon is used in the encounter, people often focus on the weapon, as opposed to facial features or other identifiers, increasing the likelihood of a mistaken identification;
  2. Reduced reliability of cross-racial identifications – when the witness is identifying a person of a different race, the likelihood of a mistaken identification increases;
  3. Decreased accuracy of witnesses in high stress/trauma situations - often when confronted with a life or death situation, the mind focuses on survival and often does not account for details it might normally perceive, making identifications less accurate;
  4. Increased risk of mistaken identification when police do not warn a witness that the perpetrator may or may not be in the photo array of mug shots – when police show a witness a series of photographs and do not warn the witness that the perpetrator may not appear in those photographs, the eyewitness may assume that the police know who it is and therefore pick out the person who looks most similar to the actual perpetrators, even if it is the wrong person; and
  5. The lack of a strong correlation between witness statements of confidence and witness accuracy - in court, the eyewitness identification always seems so sure, but the eyewitness’s belief that he picked the right person does not actually mean he is accurate in his selection. In fact, no correlation  between confidence and accuracy in the selection exists with an eyewitness identification.

At this point, this list of factors is not exhaustive. Where appropriate, the courts may consider other factors in determining whether to allow an expert testify as to the psychology behind an eyewitness identification. The trial court ultimately will decide whether to permit expert psychological evidence regarding eyewitness identification and will decide on a case by case basis.

By Matthew Quigg