The recent execution of Troy Davis, an African American man convicted of murdering a police officer, brings into question the accuracy and procedures of our current justice system. Our justice system bases its convictions on expert and eye-witness testimony rather than on empirical data.
In the case of Troy Davis, his conviction and subsequent execution were based almost entirely on eye-witness testimony. Unfortunately for Troy Davis, Psychology has long known the fallibility of eye-witness testimony. Eye-witness testimony can be swayed by subtle cues from interrogators, the way the line-ups were presented, and subsequent discussions and recall of the events.
It has been reported in the news media that in the case of Troy Davis that the eye-witness accounts were subject to all kinds of problems that could easily have altered people's memory of the event. For example, it was reported that police placed wanted posters of Troy Davis in the neighborhood, cued witnesses as to who they expected the witness to pick from the line-up, and creating a mock-up of the event. These factors could have easily produced false memories of Troy Davis' role in the shooting of the police officer. Out of the nine eye-witnesses who identified Troy Davis as the killer, seven individuals have subsequently retracted their testimony. They are no longer confident that he was the real killer.
How can we execute a man based solely on eye-witness testimony when we know that such testimony can be so flawed? What if we just killed the wrong man? Perhaps, we should rethink how our justice system uses information to convict individuals. I believe we should focus more on verifiable evidence and focus less on eye-witness testimony which is so often intrinsically flawed.
For a good review of our knowledge of eyewitness testimony and its flaws see this article.