Factual background: On December 24, 1983, two men abducted a woman in the parking lot of a shopping mall. The victim was forced into the back seat of her car where one man pinned her arms and legs while the other drove. The driver stopped in a residential area where both men repeatedly assaulted her sexually. She was ordered out of her car, then the men drove away. The second assailant was never identified.

In September 1984 a Union County jury deliberated one day and found David Shephard guilty of rape, robbery, weapons violations, and terrorist threats. Shephard was sentenced to 30 years in prison.

Prosecutor's evidence at trial: The prosecution based its case on several points:

· The victim identified Shephard by sight and voice at his work.

· The victim heard one of the attackers call the other man Dave.

· The victim's purse and car were found near the airport building where Shephard worked.

· Blood test results showed that Shephard's antigens and secretor type matched those of the assailant.

· Shephard's alibi was uncorroborated and was punctured by the prosecution in cross-examination.

Postconviction challenges: Shephard filed court papers in 1992 requesting that all evidence containing semen samples be released for DNA tests. The prosecution agreed.

DNA results: The first DNA test indicated that one discernible semen stain on the vaginal swab from the rape kit did not match Shephard's. But the defendant was not vindicated because there had been two rapists. A second test revealed a second DNA sample that was too faint to read.

Shephard's defense attorney then asked the laboratory if any samples could be found on the panty liner the victim was wearing at the time of the attack. This test found two distinct DNA patterns, neither of which matched Shephard's. Subsequent testing, at the prosecutor's request, of the victim's boyfriend (the only person she was having consensual sex with at the time) showed that the boyfriend did not match either of the samples from the panty liner.