NEW YORK (AP) - The New York City medical examiner's office confirmed Friday that it is reviewing hundreds of rape cases for possible errors in DNA analysis.
Officials said it appears so far that the testing in the vast majority of the cases was valid. But in one instance, the review uncovered evidence that resulted in an indictment last year accusing a man of raping a minor more than a decade ago in Brooklyn.
Local politicians responded to news of the mishandled sex crimes evidence, first reported in The New York Times, by saying it suggests more victims may have been denied justice. The City Council announced it would hold an oversight hearing later this month.
"We cannot allow these women to wonder if their attacker remains free or to go one more day without knowing justice was served in their case," City Council Speaker Christine Quinn said in a statement.
The review began after the medical examiner's office discovered errors by an unidentified laboratory technician, who was hired in 2001 and resigned in 2011, office spokeswoman Ellen Borakove said.
During a training session before her resignation, supervisors learned that her "work wasn't up to the standards we expect," Borakove said.
The medical examiner's office determined that the technician had handled evidence in more than 800 sexual assault cases during her nine-year tenure. The review, which is more than half-way completed, so far has found that she failed to detect existing biological evidence in at least two dozen instances.
While the review recreates the possibility of new charges being brought in old cases, the offices of Brooklyn District Attorney Charles Hynes and Manhattan DA Cyrus Vance Jr. said Friday that there was no indication the faulty work resulted in convictions of innocent people.
No cases "were affected by the errors of this employee," said Vance spokeswoman Erin Duggan.
Duggan said that "as a measure of transparency," prosecutors alerted defense attorneys involved in cases where the employee had contact with forensic kits.
"The retesting of these false negatives did produce a few new samples of DNA. However, to date no offenders have been identified," Duggan said.
In seven of the cases under scrutiny, new DNA profiles were developed. One new profile matched a convicted offender's sample, leading to the indictment in the pending Brooklyn rape case. In two other instances, the new DNA evidence was linked to people already convicted or under suspicion.
The medical examiner's office employs 48 technicians who do preliminary processing of evidence to determine if a suspect left behind saliva, semen or blood. The workers are responsible for placing swabs from victim's bodies into test tubes, and for examining underwear and other clothing for signs of stains that should be tested for DNA.
In some instances, the technician in question reported she found no potential DNA evidence on clothing, according to a summary of the review. Re-examinations by other analysts found stains that tested positive for blood and semen.
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