Over the last decade, the field of forensics has been thrown into disarray. In the US, Australia and elsewhere, dozens of lab scandals have called into question literally thousands of legal verdicts, in a development that threatens to overwhelm entire legal jurisdictions.
At the same time as they wreak havoc on judicial processes, these revelations also challenge us to re-examine personal assumptions that have been with us from birth. Are fingerprints unique? Should we place any more trust in what 'expert witnesses' tell us than in the accounts of laypeople? Going by recent events, we'd be right to feel circumspect about these and many other claims of forensic 'science'.
The FBI recently admitted flaws in forensic evidence in cases spanning decades. Of 28 examiners with the FBI Laboratory’s microscopic hair comparison unit, 26 overstated matches in ways that favoured prosecutors in more than 95 percent of cases reviewed so far, including 32 capitol cases that resulted in executions.
But this problem is not limited to one country; similar revelations are now surfacing around the globe, and whole forensic disciplines are being called into question. Bite mark analysis has already been banned from the courtroom in several jurisdictions, whole labs have been shut down, and reviews are underway in many other areas.
We discuss the deep philosophical implications of this, and talk to Sarah Chu from The Innocence project, who are working to acquit wrongly convicted people whose lives have been ruined by the bungling of forensic analysts.