New York investigating evidence errors in 843 rape cases

In an unusual move, the New York medical examiner is reviewing hundreds of rape cases where a lab technician mishandled or overlooked DNA evidence. In some instances, the errors caused criminal investigators to make cases on bad information.

The Medical Examiner’s Office has already uncovered 26 cases where a lab technician overlooked DNA evidence, The New York Times reports. One of those cases led to a criminal indictment a decade after the piece of evidence was initially collected, while two other cases allowed investigators to link suspects to old crimes.

The technician whose work is being audited worked for the agency for nine years before resigning in November 2011. Speaking of the initiative, which began in March 2011, medical examiner’s spokeswoman Ellen Borakove told The Times, “This is the first time we’ve had anything like this.”

The cases under review span from 2001 to 2011.

And the examiners involved are still not sure how extensively the problem of mishandled DNA evidence may reach. One more than one occasion, supervisors believed they had completed a review of the technician’s errors — only to discover more and more cases requiring reassessment.

Most commonly, the technician — who was responsible for collecting DNA evidence from sex crime victims’ bodies at the hospital, and putting it in test tubes for more experienced lab workers to analyze — missed stains caused by biological material, or identified them but then bungled a chemical analysis. She also apparently accidentally mixed DNA from 19 separate investigations, the report says.

Such mistakes are no small matter, and could lead to a report claiming no evidence where in fact there had been, or vice versa.

The agency still has 412 cases to review out of a total 843.

A Medical Examiner’s Office attorney said the agency was “leaving no stone unturned” in reviewing casework handled by the technician.

Though the technician’s mistakes could plausibly have caused numerous wrong acquittals, doctors involved said that they did not lead to any wrong convictions.