Exonoration Statistics

Exonerations in the United States, 1989 through 2003

SAMUEL R. GROSS
University of Michigan Law School
KRISTEN JACOBY
University of Michigan Law School
DANIEL J. MATHESON
University of Michigan at Ann Arbor - Law School
NICHOLAS MONTGOMERY
University of Michigan at Ann Arbor
SUJATA PATIL
Children's Hospital of Philadelphia

Journal of Criminal Law and Criminology, Vol. 95, No. 2, 2005

Here's the abstract:

In this paper we use reported exonerations as a window on false convictions generally. We can't come close to estimating the number of false convictions that occur in the United States, but the accumulating mass of exonerations gives us a glimpse of what we're missing. We located 340 individual exonerations from 1989 through 2003, not counting at least 135 innocent defendants in at least two mass exonerations, and not counting more than 70 defendants convicted in a series of childcare sex abuse prosecutions, most of whom were probably innocent. Almost all the individual exonerations that we know about are clustered in the two most serious common felonies: rape and murder. They are surrounded by widening circles of categories of cases that include false convictions that are rarely detected, if ever: rape convictions that have not been reexamined with DNA evidence; robberies, for which DNA identification is useless; murder cases that are ignored because the defendants were not sentenced to death; assault and drug convictions that are forgotten entirely; misdemeanor convictions that aren’t even part of the picture. Judging from our data, any plausible guess at the total number of miscarriages of justice in America in the last fifteen years must run to the thousands, perhaps tens of thousands, in felony cases alone. We can, however, see some clear patterns in those false convictions that have come to light. For rape the dominant problem is eyewitness misidentification - and cross-racial misidentification in particular, which accounts for the extraordinary number of exonerations in rape cases with black defendants and white victims. For murder, the leading cause of the false convictions we know about is perjury - including perjury by police officers, by jailhouse snitches, by the real killers, and by supposed participants and eyewitnesses to the crime who knew the innocent defendants in advance. False confessions also played a large role in the murder convictions that led to exonerations, primarily among two particularly vulnerable groups of innocent defendants: juveniles, and those who are mentally retarded or mentally ill. Almost all the juvenile exonerees who falsely confessed were African American. In fact, one of our more startling findings is that 90% of all exonerated juvenile defendants were black or Hispanic, an extreme disparity that, unfortunately, is of a piece with racial disparities in our juvenile justice system in general. Nearly a quarter of exonerated defendants had been sentenced to death, despite the fact that death row inmates make up only about one-quarter of one percent of the population American prisoners, and a much smaller proportion of the those who pass through our prisons over time. This appears to reflect two simultaneous patterns: capital defendants are more likely to be convicted in error, and false convictions are more likely to be detected when the defendants are on death row. That means that capital defendants who are not sentenced to death, or defendants in similar murder prosecutions in which the death penalty was not sought, may be in the worst position of all: they may suffer the same high risk of false conviction as death row inmates, but get no benefit from the comparatively high chance of exoneration after conviction.