15 June 2017 :

An examination of data from the more than 30 death-row exonerations in the past decade shows that most common causes of wrongful convictions in death penalty cases are official misconduct and perjury/false accusation. Many factors contribute to wrongful convictions, and it is no different in capital cases. But the most recent data from the National Registry of Exonerations points to two factors as the most overwhelmingly prevalent causes of wrongful convictions in death penalty cases: official misconduct and perjury or false accusation. As of May 31, 2017, the Registry reports that official misconduct was a contributing factor in 571 of 836 homicide exonerations 68.3%, very often in combination with perjury or false accusation, which also was a contributing factor in 68.3% of homicide exonerations. According to the Registry, mistaken witness identification was present in nearly a quarter of homicide exonerations (203, 24.3%), as was false or misleading forensic evidence (194, 23.2%), and false or fabricated confessions were present in more than a fifth of the exonerations (182, 21.8%). The Registry lists inadequate legal representation at trial as a contributing factor in more than a quarter (218, 26.1%) of these wrongful homicide convictions. Two reports released on March 7, 2017 by the National Registry of Exonerations, Exonerations in 2016 and Race and Wrongful Convictions in the United States, provide continuing evidence of the role of official misconduct in wrongful capital prosecutions, and suggest a link between race of defendant and official misconduct. The Registry's annual report on exonerations revealed a record 166 exonerations in 2016—and a record number of exonerations involving police or prosecutorial misconduct. 54 of the 2016 exonerations—nearly a third—involved wrongful homicide convictions. At least 13 of these cases involved the wrongful use of the death penalty—meaning that the death penalty played a role in nearly a quarter of the 54 homicide exonerations in 2016. Every one of these wrongful convictions involved either official misconduct or perjured testimony/false accusation, and eleven (84.6%) of them involved both. The National Registry's race report documents that the "rate of official misconduct is considerably higher among murder exonerations with black defendants than those with white defendants, 76% compared to 63%. The rate of misconduct is higher overall in capital cases, and the difference by race is greater: 87% of black exonerees who were sentenced to death were victims of official misconduct, compared to 67% of white death-row exonerees.