Man Challenges DNA Murder Conviction

DNA evidence is considered to be positive proof of a crime. But are the labs that do the tests infallible? A Michigan man who was convicted for a murder that happened more than three decades ago claims the lab got it wrong.

It began in 2001 in Michigan when state detective Eric Schroeder started re-examining a murder case from 1969.

"This case had fallen through the cracks. I just didn't feel that we could give up on it," he told CBS News. "Jane Mixer deserved to have some answers."

In 1969, Jane Mixer was a law student at the University of Michigan. She posted a note on a college ride board looking for a lift from Ann Arbor to her parent's house in Muskegon, but she never made it home.

"In the early morning hours March 21, 1969, Jane's body was discovered in the Denton Road Cemetery," Schroeder said.

She had been shot twice in the head. No one was ever prosecuted for the crime. But much of the evidence was preserved.

"These are the pantyhose that were on her body," Schroeder said. "We took these to the lab, the forensic scientists took the cuttings from the areas that they located with the possible staining, and did the DNA analysis."

DNA tests that weren't available in the 1960s were used to analyze stains on Mixer's clothing, and there was a match. Gary Leiterman, a 62-year-old retired nurse, was arrested and eventually tried for murder.

"I'm a kind and gentle person," Leiterman said. "I've never been abusive to anybody."

Leiterman claimed he was innocent and prosecutors had a big problem. Other DNA had been discovered on Mixer's body as well. A drop of blood on her hand was found to match the DNA of a convicted killer named John Ruelas. But Ruelas was 4 years old at the time of the murder. Since the Ruelas and Mixer cases had been processed in the same crime lab at around the same time the defense believed the results had been contaminated.

Nevertheless Leiterman was found guilty of murder. He is appealing and his attorney feels he has a shot.

"The fact that there is not just some biological material but a blood drop from a person who was 4 years old at the time, I think calls into question the entire reliability of the testing in this case," attorney Mark Satawa said.

Leiterman's wife, Solly, told The Early Show co-anchor Julie Chen that she felt the jury simply gave up.

"Oh, all I can tell is it went on for several days, the jury was tired of everything," she said. "It's Friday afternoon. Let's go home and let's close this case and it never was really closed. Never really closed. That's no closure. No closure. It's a false conviction."

But prosecutor Steven Hiller says justice was served.

"John Ruelas' blood doesn't change Gary Leiterman's DNA having been on the victim," he said. "Gary Leiterman deserves to pay the price for what he has done."

But Solly Leiterman says the lab was contaminated.

"I have read the reports," she said. "I'm a registered nurse. I've read this report. I looked at the trial transcript. I read it over and over. And nothing in that trial, nothing in that trial really revealed that this man, my husband of 30 years, had anything to do with his murder."

Satawa says he will appeal the case, which is based on the reliability of DNA evidence.

"Without that evidence, Gary Leiterman is a free man today. And that's really the thrust of the entire case and the thrust of the entire appeal," Satawa said. "I've been a lawyer for 16 years and I've never had a case where I've felt more strongly on the innocence or the correctionness of my side than this case. You look at the DNA in this case. It is incomprehensible to me that Gary Leiterman would ever be charged, let alone convicted, based upon the unreliability and the absurdity of the DNA and the argument the prosecutor made in connection with this case."

Solly Leiterman says she and her husband are closer than ever and they speak every day.

"He is just devastated," she said. "This man has lived a very productive life. He's a very loving person. He's dedicated to his kids. He could not have done this. Nothing in our life could tell me that this man is capable of something like this."