DNA doesn't offer magic key to case

Found in minority of assault cases

For more than two weeks, Durham waited for the results of DNA tests expected to identify or exonerate the Duke University lacrosse players who a woman said raped her at a team party.

Lawyers representing some of the 46 players tested said the tests found no matching DNA on or in the woman. They contend that the results prove that no rape or sexual intercourse took place.

But the prosecutor disagrees, and the case isn't settled.

According to a U.S. Department of Justice study, DNA evidence from an attacker is successfully recovered in less than a quarter of sexual assault cases. A spokesman for Duke Hospital, where the accuser was treated March 14, would not discuss the specific evidence provided to Durham police.

Typically, when a woman reports that she has been sexually assaulted, hospital workers collect what is known as a "rape kit" -- samples of semen, blood, hair and pubic hair. If the attacker wears a condom, doesn't ejaculate or penetrates the victim with a foreign object, semen or other sources of DNA are unlikely to be collected.

"DNA is an extremely reliable form of evidence, when it's there," said Rich Rosen, a UNC-Chapel Hill law professor who works with the N.C. Actual Innocence Commission, a group that examines wrongful convictions. "In a lot of cases, there is nothing there, and often we don't know why nothing is there."

Durham District Attorney Mike Nifong has said he thinks that an assault occurred and that any assailants might have used condoms. Joseph B. Cheshire V, a Raleigh lawyer who represents one of the four team captains, said if that were true, forensic tests would have shown evidence of latex or spermicide. A spokeswoman for the State Bureau of Investigation declined to discuss what tests might have been performed on the vaginal and anal swabs collected from the accuser at the hospital.

Even if a DNA sample is collected, it does not prove the guilt of a particular individual with the level of certainty often depicted on television crime dramas. Samples can be mishandled, mislabeled or contaminated.

"The best use of DNA is excluding someone as the source of a particular sample," said Mark Rabil, a Winston-Salem lawyer who represented Darryl Hunt, a man freed in part by DNA evidence after serving 18 years in prison for a 1984 rape and murder. Rabil also serves on a forensic science task force formed by the N.C. Academy of Trial Lawyers examining the use of DNA evidence in the state.

The lawyers' task force filed a complaint against the SBI lab last year after DNA tests were botched in three capital murder cases. A review by the SBI's accrediting agency, the American Society of Crime Laboratory Directors, found no wrongdoing on on the part of the lab.

"There were some problems with how the evidence was handled, but a lot of people handled that evidence before the SBI got it," said Ralph Keaton, the executive director of the accreditation board.

Nifong said Tuesday that he is awaiting additional DNA test results. The SBI confirmed that it has completed tests on all the samples provided by the Durham police to date, raising the possibility that additional samples have been sent to the FBI crime lab in Quantico, Va., or to a private facility.

No charges have been filed, though the investigation is continuing. If no additional results are forthcoming, Rabil said, Nifong will be left to explain at trial why there was no DNA match.

"It certainly favors the defense more than the prosecution," Rabil said of Monday's reported results. "It could be used by the defense to plant reasonable doubt in the minds of a jury."