IT IS HARD for most people to imagine being convicted of a crime they did not commit. Yet this scenario is not only possible, but far more likely than it should be. Sometimes it is just a matter of being in the wrong place at the wrong time, or witnesses mistaking what they thought they saw. Perhaps you were the last person to see the victim alive, and the police suspected you and did not follow other leads, or your lawyer did not provide an adequate defence, or the prosecution did not inform the defence of contrary evidence. Or perhaps the evidence was flawed. Many circumstantial cases still result in a conviction, despite the criminal justice system demanding guilt beyond reasonable doubt.

Systemic factors regularly result in the conviction of innocent people: incorrect eyewitness identification, tunnel vision, bad lawyering, withholding exculpatory evidence, incorrect scientific evidence, false confessions, informant/snitch testimony. Eyewitness identification, which can so convincingly influence a jury, is the major factor in wrongful convictions later corrected by DNA evidence in the United States.