Columbia Law Review recently released "Judging Innocence" by Brandon Garret.  Here is the summary:   

This empirical study examines for the first time how the criminal system in the United States handled the cases of people who were subsequently found innocent through postconviction DNA testing. The data collected tell the story of this unique group of exonerees, starting with their criminal trials, moving through levels of direct appeals and habeas corpus review, and ending with their eventual exonerations.

Beginning with the trials of these exonerees, this study examines the leading types of evidence supporting their wrongful convictions, which were erroneous eyewitness identifications, forensic evidence, informant testimony, and false confessions. Yet our system of criminal appeals and postconviction review poorly addressed factual deficiencies in these trials. Few exonerees brought claims regarding those facts or claims alleging their innocence. For those who did, hardly any claims were granted by courts.

Far from recognizing innocence, courts often denied relief by finding errors to be harmless. Criminal appeals and postconviction proceedings brought before these exonerees proved their innocence using DNA testing yielded apparently high numbers of reversals a 14% reversal rate. However, that reversal rate was indistinguishable from the background reversal rates of comparable rape and murder convictions. Our system may produce high rates of reversible errors during rape and murder trials.

Finally, even after DNA testing was available, many exonerees had difficulty securing access to testing and ultimately receiving relief. These findings all demonstrate how our criminal system failed to effectively review unreliable factual evidence, and, as a result, misjudged innocence. [Mark Godsey]