Causes
There are many reasons why wrongful convictions occur. The most common reason is false eyewitness identification, which played a role in more than 75 percent of wrongful convictions overturned by the Innocence Project. Often assumed to be incontrovertible, a growing body of evidence suggests that eyewitness identifications are unreliable.
Unreliable or improper forensic science played a role in some 50 percent of Innocence Project cases. Scientific techniques such as bite-mark comparison, once widely used, are now known to be subjective. Many forensic science techniques also lack uniform scientific standards.
In about 25 percent of DNA exoneration cases, innocent people were coerced or threatened into making incriminating statements or false confessions. Of the 292 people freed by the Innocence Project, 28 actually pled guilty to crimes they did not commit (usually to avoid a harsher sentence, or even the death penalty).
Government misconduct, inadequate legal counsel, and the improper use of informants also contributed to many of the wrongful convictions since overturned by the Innocence Project
Read more about this topic: Innocence Project