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- Published: 01 April 2012
- Written by Dr. Marvin Zalman
The Classic Study that Defines and Examines the Exonerations of Actually Innocent People
Samuel R. Gross, Kristen Jacoby, Daniel J. Matheson, Nicholas Montgomery & Sujata Patil
Exonerations in the United States, 1989 Through 2003.
Journal of Criminal Law & Criminology 95(2):523-60 (2005)
This foundational article reports on a study utilizing snowball methodology which uncovered 340 official exonerations between 1989 and 2003. The exonerations occurred in four ways: (1) pardons issued by governors or other executive officers based on evidence of innocence (42 cases); (2) criminal charges dismissed by courts after new evidence of innocence emerged (263 cases); (3) acquittals on retrial based on evidence that the defendants had no role in the crimes for which they were originally convicted (31 cases); and (4) the state posthumously acknowledged the innocence of defendants who died in prison (4 cases).
Because there is no national registry of exonerations or any simple way to tell from official records which dismissals are based on innocence, information for these 340 exonerations were drawn from media reports and other fortuitous sources.
Sixty percent of the exonerations were in murder convictions, 36% for rape, 3% for other violent crimes, and 1% for drug and property crime convictions. DNA exonerations accounted for 144 cases while 195 exonerations were based on other kinds of evidence. Most of the DNA exonerations (105) occurred in rape cases, which helps to explain the high proportion of rape exonerations. The large number of murder exonerations is explained by the high level of attention devoted to reviewing those cases and the likelihood that false convictions are more likely to occur in murder and especially in death penalty cases than in other criminal prosecutions.
More than 300,000 prisoners were in prison in 2001 for robbery, assault, and other violent felonies, and over 600,000 for property, drug and public order offenses. Prior studies show that eyewitness misidentifications occur more frequently in robbery cases. This suggests that false convictions that come to light are the tip of the iceberg, and that thousands of wrongful convictions for other crimes must occur.
The number of known exonerations grew steadily from 11 in 1989, to 23 in 1999, to 44 in 2003. This increase was probably due to more states adopting post-conviction DNA testing laws and an increasing number of innocence projects. The study did not include innocent defendants who were not exonerated because their cases were pending, they pleaded guilty to be released from prison, or the state simply failed to exonerate obviously innocent people. Cases of mass exoneration were also excluded.
Mistaken eyewitness identification was prevalent in the rape exonerations. The common factor in murder investigations was witness perjury. False confessions were most common among juvenile, mentally ill, or mentally retarded exonerees. The racial composition of murder exonerees matched the racial composition of inmates imprisoned for murder. Black exonerees falsely convicted for raping white women, however, were over-represented among those falsely convicted of rape and exonerated (mostly by DNA). Given the infrequency of inter-racial rape, the most obvious explanation is the peril of cross-racial identification.