FORENSIC PSYCHOLOGY
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Are Eyewitness testimonies always accurate?
Imagine a scenario where a crime happens and the police search for evidence. A few days after struggling for a breakthrough, the police find a person who claims to have witnessed the crime and can identify the perpetrator. This halts the ongoing search for evidence, the person identifies the perpetrator, and the case is closed.
An eyewitness gives a whole new direction to the case. “I have seen the one committing the crime. I can identify the one you’re looking for”. Probably the words every detective wants to hear. An irrefutable piece of evidence, an eyewitness testimony. Seems foolproof.
Unless.
What if the person is wrong? What if they don’t actually remember? What if it was a mistake? What if it was a guess? What if an innocent got convicted?
Can you sense yourself feeling a little bad for the one who's been sentenced based on the testimony now? So yes, eyewitnesses can be wrong and hence ‘Eyewitness Testimony is the Best Kind of Evidence’ is actually a myth.
Eyewitnesses, of course, can also be very accurate in their descriptions, despite failing to identify offenders precisely. Very little research is available that compares the characteristics of offenders with those descriptions given to the police. What evidence there is suggests that witnesses can be accurate in terms of describing individual characteristics, but are not always so.
We can take the example of the Anna Lindh murder case (Granhag et al., 2013). The stabbing, which lasted for 15 seconds, was witnessed by 29 people, mainly women. Each one was interviewed up to five times by the police. Descriptions of the offender provided by the witnesses were the main data for the study. One notable event in the course of the study was that the police released pictures of the suspect three days after the killing – some witnesses were interviewed both before and after the release of pictures. The availability of CCTV video of the offender a few minutes before the attack provided the baseline information of the offender characteristics for the researchers. Overall, the eyewitness descriptions of the killer as recorded by the police included a total of 43 different unique attributes, grouped into 20 categories and then into four broad categories – clothes, face, hair and general. The accuracy of the details provided was coded into the categories of correct, partly correct, incorrect, and not verifiable. Findings revealed that the accuracy of the witnesses was not good. Only 35 percent of the details provided were correct, with 24 per cent of it being only partly correct. This left a high percentage of details which were actually misleading or potentially misleading in the investigation. The release of pictures to the media did result in more details being provided to the police than before. But the increase was confined to details about clothing and not anything else.
Despite CCTV evidence, how did such a disparity come about?
This is because subsequent events influence testimony about incidents.
Witnesses to a crime may be exposed later to new information. In some circumstances, the new information can influence how they recollect the incident. Furthermore, information in one modality may affect memory for events held in a different modality i.e. verbal information may affect visual recall.
Elizabeth Loftus, cognitive psychologist and expert on human memory, has talked in length about eyewitness testimony and how reliable is our memory.
Can Eyewitness Testimony Contribute To Wrongful Convictions?
At a trial, the testimony of an eyewitness who incriminates the defendant is—along with the presence of a confession—usually the most influential evidence. If a jury or a judge believes eyewitnesses who have testified in good faith, the belief leads to a conclusion of guilt. Alibis, circumstantial evidence, even masses of physical evidence favoring the defendant’s innocence, can wither away in light of an eyewitness’s courtroom identification. So yes, eyewitness testimonies can and have contributed to wrongful convictions. Wells (1993) concluded that eyewitness errors provide the single most frequent cause of wrongful convictions.
A recent review by the US Dept. of Justice extended those exonerated on the basis of DNA testing to over 100, and found that eyewitness error was involved in 84% of the cases of wrongful conviction. As of September 2007, the total number of these cases was 207 and these cases cover only post-conviction DNA exonerations. For every one of those, there are many others that are caught at the pretrial stage and never get to trial because the charges are dismissed by prosecutors.
Most recent case of eyewitness inaccuracy is of Lydell Grant who was sentenced to life in prison in 2012 for the murder of a young Texas man based on the lineup identification of six eyewitnesess.
Eyewitness identification can be influenced in a lot of ways, most common being hints given by police. Prominent psychologist Elizabeth Loftus had termed it as unconscious driving of people by the police into having false memories. Fast forward to a decade, Grant was released from prison in 2021 when Jermarico Carter confessed to the killing after DNA testing evidence found him guilty.
The availability of DNA technology has given a whole new impetus to the analysis of claims of wrongful conviction. In India, the amendment to the Code of Criminal Procedure, 1973, now the Criminal Procedure Code (Amendment) Act of 2005, gives emphasis to the collection of DNA samples from both the accused and the victim in criminal cases.
Nevertheless eyewitness identifications are still considered to be the backbone of most police investigations and courtroom decisions till date.
factors predicting accuracy
References
1. Fulero, S.M., & Wrightsman, L.S. (2009). Forensic Psychology 3rd Edition
2. Howitt, D. (2018). Introduction to Forensic and Criminal Psychology Sixth Edition.