Police handout Jason Ryan, left, was arrested Tuesday in the 1996 murder of Geraldine Montgomery of Kalkaska, Mich. Jamie Lee Peterson, right, is serving a life sentence after being convicted of killing Montgomery.

The arrest of a Michigan man in a horrific 17-year-old rape-murder case has reopened old wounds for the victim’s family and cast fresh doubt on the guilt of the man who was convicted of the crime and sentenced to life in prison.

Michigan State Police on Tuesday arrested 35-year-old Jason Anthony Ryan, of Davison, Mich., and charged him with homicide. Legal sources tell NBC News the arrest occurred after a DNA test of semen found at the scene of the murder matched Ryan’s profile in a national database.

The rape and murder of Geraldine Montgomery, a 68-year-old widow, was the worst crime in memory in Kalkaska, Mich., a town of about 2,200 residents in the northern reaches of the state. In October 1996, someone broke into her home in the village, beat and raped her, then shoved her into the trunk of her running Buick sedan and left her to asphyxiate.

Investigators homed in on Jamie Lee Peterson. In a series of interrogations, the 23-year-old, already in jail on a sex charge and with a long history of mental illness, confessed. Despite quickly recanting, he was tried, convicted and sentenced to life in prison without the chance of parole.

The outcome notwithstanding, Peterson’s defenders insist the now 39-year-old had nothing to do with Montgomery’s murder.

“We are completely convinced that he is completely innocent,” said Joshua A. Tepfer, an attorney at Northwestern University’s Center on Wrongful Convictions, which has assisted in a number of the 311 post-conviction DNA exonerations in the U.S. and is working with the Michigan School of Law’s Innocence Clinic to represent Peterson. “This is a story about tunnel vision.”

The arrest of Ryan appears to bolsters that claim.

During the original investigation, police interviewed more than 100 people in Kalkaska County, population 15,000. Among them was Ryan, then an 18-year-old convicted felon, who provided a DNA sample that apparently was never tested. Police ruled him out as suspect after he passed a polygraph test.

'Just a good person'

In a town in which murders can be counted on one hand, no one has forgotten the killing of Geraldine Montgomery.

“She was just a good person,” said her daughter Patty Cox, 67. “She was very involved in her church. I don't know of anyone who disliked her. There was no reason to dislike her, because she was helpful and involved in the community.”

Montgomery spent two decades working as a teacher’s aide before retiring in 1994 to a life of church events and craft fairs, which is how she spent Saturday, Oct. 5, 1996, the last day of her life.

When Montgomery didn’t show up for church on Sunday, Cox and her husband, Michael, went to her home in the middle of town and found her car parked in the garage, running. They called 911.

Montgomery’s death shocked Kalkaska -- a close-knit community where whitetail deer hunters gather each winter and tourists flock each summer -- and made villagers begin to lock their doors at night.

Sometime around 8 p.m. the previous night, police said, an intruder broke into Montgomery’s single-story house on West Dresden Street. There were signs of struggle. A lamp was broken, and Montgomery’s bra had been ripped and left in the laundry room. Investigators determined she was sexually assaulted in the living room, then taken to the garage and locked in the trunk of her car.

It was a senseless and brutal crime. Montgomery was arthritic, just 4-feet, 11-inches tall and a little over 110 pounds. Only a few things were missing from the house -- $30 from her wallet and a candle.

The perpetrator wiped away prints, but investigators found two samples of semen -- one in the victim’s vagina, and one, mixed with saliva, on her shirt. The evidence was tested for DNA.

Kalkaska police teamed with the Michigan State Police on the investigation. By the end of 1996, they had six suspects, but all were ruled out by the DNA evidence.

Then, in February 1997, an inmate at the county jail contacted police with a possible lead. He said a fellow inmate, Jamie Peterson, had been claiming he committed the most notorious crime in the county’s history.

Investigators brought in Peterson, who was serving time on a statutory rape charge for having sex with a 15-year-old girl, for questioning. He failed a polygraph test and confessed to the crime. Even before he was arrested, Kalkaska’s sheriff announced that they had their guy -- an effort, according to the local paper, “to soothe the jangled nerves of a community.”

Days later, Peterson, who had spent years moving between psychiatric wards and juvenile group homes, recanted. He said he had made up the story to get sent to a state hospital. “The DNA’s going to come back not mine,” Peterson said, according to transcripts of the interview. “And I got witnesses that state where I was that night.”

Investigators insisted that Peterson knew details, such as how much money was taken, that were impossible to know if had not committed the crime.

“I believe that the DNA ... it’s going to come back to you,” said Det. Sgt. Greg Somers, of the Michigan State Police.

“You have nothing to worry about if the DNA doesn’t come back to you,” he added.

Police shift their theory

But when the DNA evidence did not match Peterson’s, police shifted their theory. Instead, they now maintained, he’d had a partner in the crime.

Peterson appeared to go along with the new theory. In further interviews, he said he had committed the crime with a male friend. Then, when that man was cleared, Peterson portrayed the crime as a burglary-gone-wrong, hatched by a female friend and her boyfriend. He said he had lied before because they threatened to hurt his girlfriend.

“When he started confessing, it was like a gift from heaven,” said Bob Carey, Peterson’s trial lawyer who has long maintained his client is innocent. “Then when the DNA results came back, they weren’t going to let that stand in the way.”

Carey argued throughout the case that Peterson's was a false confession. Though virtually unheard of at the time, subsequent study has developed evidence that false confessions are common. Some 25 percent of wrongful convictions involve false confessions, according to The Innocence Project.

In April, six weeks after announcing their inquiry had narrowed to a single man, investigators issued a press release stating that they now believed “more than one individual was involved in the death of Geraldine Montgomery.” Villagers who had just begun to settle again into normal life were cautioned to continue to lock their doors.

Limits to DNA technology at the time lent some credence to the new theory. Investigators had two body fluid samples – one that was sufficient to provide a full DNA profile, another – from the stain on Montgomery's blouse -- was not. They theorized that the untestable second sample pointed to Peterson, while the first belonged to his unidentified accomplice.

The prosecutor would later say that accomplice was a tall blond man, based on the account of a witness who saw a man matching that description through the window of Montgomery's house the night of the murder. Peterson was short and had dark hair.

Investigators searched for a second man, interviewing and DNA testing several people linked to Peterson. They spoke to others, in and out of jail, who seemed likely candidates. In July, they brought in a 19-year-old jail inmate named Jason Ryan.

Ryan was a wanderer, living, his aunt told police, “here and there.” He arrived in Kalkaska about a week before the murder, and was staying with an acquaintance less than two blocks from Montgomery’s house. Police questioned him in the days following Montgomery’s death.

Early next year, Ryan was arrested in Flint, Mich., and charged with felony home invasion. That April he pleaded guilty, adding to a criminal record that included a juvenile larceny charge. Then he was returned to Kalkaska, a convicted felon, to deal with a hold for an outstanding traffic court case.

When investigators questioned Ryan in early 1997, he denied knowing Peterson but acknowledged he was in Kalkaska the weekend Montgomery died.

First DNA sample vanished

Ryan told investigators he would “cooperate in the investigation in any way he could.” He offered a DNA sample and took two polygraphs. The first polygraph proved inconclusive, but the second indicated “Ryan was being truthful when he stated he was not involved with and did not have any knowledge of the Geraldine Montgomery homicide.”

Records show that Ryan’s DNA was submitted to a lab in Grayling, Mich., then apparently sent out to a second lab. It is unclear if that sample was ever tested.

That November, Peterson went to trial. It took 23 days before Peterson was convicted, and sentenced to life without the possibility of parole. He remains at Oaks Correctional Facility, a state prison in Manistee, Mich.

Carey didn’t give up on his client. Neither did Peterson’s appellate lawyer, Al Millstein, now in his 90s.

In 2012, they asked county officials to re-test the DNA. The county resisted until last May, when a new prosecutor agreed to send both vaginal and partial DNA samples for re-testing.

When those tests were done, they showed a match in the national Combined DNA Index System database, or CODIS. Lab reports reviewed by NBC News indicated that both samples were consistent with the DNA of Jason Anthony Ryan.

While the results were enough to get authorities to arrest Ryan, it’s unclear whether they will free Peterson.

A press release issued Tuesday by the Michigan State Police stated that “Peterson ultimately admitted to the crime and had information that only someone at the scene should have knowledge of. Evidence at the time of the trial indicated there were multiple subjects involved in the homicide.

“Through the use of newer technologies, a DNA profile was obtained that led to the identification and arrest of the second perpetrator.”

More coverage from NBC News affiliate WPBN-TV in Travers City, Mich.

But lawyers representing Peterson maintain there was no second perpetrator.

“This new evidence proves that Jamie Peterson is absolutely innocent, he was never in that house, committed no crimes, and has no idea who did,” said Caitlin Plummer, an attorney with the Michigan Innocence Clinic.

They said they plan to file a motion before Christmas asking for a new trial, and for Peterson’s release. The Kalkaska prosecutor’s office did not immediately respond to requests for comment.

For relatives of Geraldine Montgomery, Ryan’s arrest has brought a mixture of relief and dread.

Patty Cox, Montgomery’s daughter, said she felt “huge relief” when Kalkaska’s police chief called her the night before the arrest. “I thought well, good,” she said. “There’s no question he was there.”

But the idea that Peterson could potentially be released from prison has her wondering if she will ever feel safe in her community.

“I think Peterson was justly convicted on the evidence that was there,” she said. “There was stuff that he knew, that he had to have been there.”

“How long,” she added, “is it going to be until it’s all over?”

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