Study Finds Wrongful Conviction Rate Of 8 To 15 Percent In Sexual Assault Cases

June 21, 2012

That’s according to a study from the Urban Institute, who is touting DNA exonerations of individuals who were found guilty:

Findings released today [June 18] indicate more people remain to be cleared by the Virginia project, a groundbreaking effort aimed at identifying persons wrongfully convicted in the 15 years before DNA testing was widely available.

The institute estimates a wrongful conviction rate in sexual assault cases of between 8 to 15 percent, comparable with the results in sample testing that exonerated two people and prompted then-Gov. Mark R. Warner to order the full Virginia project in 2005.

The study has gotten approval from other sources:

Jon Gould, director, of the Washington Institute for Public and International Affairs Research at American University, said “This is the most methodologically sound study that’s been done and the rate is much higher than has been shown in other studies.”

And some critics:

Rockne Harmon, a former California district attorney and DNA expert…said the institute should have at least done a representative sampling of the old court files.

Among other things, rape victims are frequently asked if they had consensual sex within 72 hours of an assault. “Without this (kind of) information little can be said about the materiality of finding a matching or non-matching DNA profile,” said Harmon.

Here’s the methodology:

The Justice Policy Center of the Urban Institute studied the test results in 634 of the Virginia cases involving 715 convicted people from 94 Virginia localities under the terms of a $4.5 million federal grant that paid for most, but not all, of the state testing.

Of the 634 cases, 422 were for sexual assault. In 227 of those cases, testing results were sufficient to either implicate or fail to find the convicted person’s DNA. And the institute believes that the testing in 33 of the exclusion cases supports innocence.

Comparing the 33 with all 422 sexual assault convictions yields an 8 percent wrongful conviction rate while comparing it to just the 227 cases where testing either implicated the convicted person or failed to find his or her DNA yields a 15 percent rate.

In 2005 the initial state sample testing of 31 cases resulted in 16 cases where the convicted person’s DNA was either identified or excluded and exonerated two men of rapes.

Comparing the two exonerations to the 31 cases yields a wrongful conviction rate of 6 to 7 percent while comparing the exonerations to the 16 cases with determinative results yields a rate of 12 to 13 percent.

Previous attempts to quantify wrongful convictions have varied depending on the nature of the crime involved. One study found a wrongful conviction rate of 3.3-5 percent in cases involving capital crimes. But what is unique about the UI study is that it’s a much higher rate than most studies have found in the past, for any crime. If future studies replicate these results, even using the low-end figure, it will turn Scalia’s scandalous claim of a .027 wrongful conviction rate for felony convictions claim on its head.

9:41pm | URL: http://tmblr.co/ZMMjnxNsqZ-9

(Notes: 8)