The family of a 20-year-old Minnesota woman killed in 1985 during a trip to upstate New York is begging law enforcement to advance the nearly four decade old cold case.

Phyllis O’Connell, mother of deceased Kristin O’Connell, wants officials to analyze more than 300 pieces of evidence using touch DNA technology with assistance from a production company, but police have denied their requests to source outside help in the ongoing investigation.

"I promised my daughter I’d never rest until that person was arrested who murdered her," Phyllis O’Connell told Fox News Digital. "That’s been my challenge for 35 years to try to find out who did this. I’m never going to give up ‘til I die. I want to know who did it — why they did it. I mean, my God. She wouldn’t have hurt a fly."

Kristin O'Connell (Credit: Jolynn Rice)

Kristin O'Connell  (Credit: Jolynn Rice)

O'Connell described her daughter as kind, outgoing and charitable. She recalled a time when Kristin volunteered to babysit the children of women staying at a shelter for domestic abuse victims while she was in high school. O'Connell shared her concerns but ultimately allowed her daughter to take on the job after Kristin insisted.

When Kristin was a college student in August of 1985, she traveled from Minnesota to a town near the Finger Lakes in New York called Ovid to meet up with a man she met on Captiva Island off the coast of Florida over spring break that same year.

Two days after arriving in Ovid on Aug. 15, Kristin called her mother to tell her she wanted to come home. 

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"She said, ‘Mom ... I decided to leave. I’m going to come home,'" O’Connell said of the phone call. O'Connell added that her daughter was going to stop and visit some friends in Boston before heading home and told her everything was "alright."

Kristin O'Connell (Credit: Jolynn Rice)

Kristin O'Connell  (Credit: Jolynn Rice)

Thirteen hours after their phone call, the young man Kristin had gone to meet — Jim Vermeersch — reported her missing to local law enforcement.

Vermeersch apparently alleged that the 20-year-old had left his trailer between 11 p.m. on Aug. 15 and 12 a.m. on Aug. 16 to take a walk by herself without shoes or a purse in the unfamiliar town, according to O’Connell. Vermeersch and some others were smoking marijuana in his trailer, which may have made Kristin uncomfortable, her mother said.

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Police discovered Kristin’s naked body in a cornfield and her bloodied clothing nearby on Aug. 16, 1985. No arrests have been made in connection with the case, though witnesses say they heard a scream the night of Aug. 15 and did not report it to authorities. Witnesses have also said they saw Kristin talking to two unidentified men on the side of the road that evening.

The local coroner determined she had been stabbed and beaten but found no signs of sexual assault and no alcohol in her system at the time of her death.

Kristin O'Connell (Credit: Jolynn Rice)

Kristin O'Connell memorial in Ovid  (Credit: Jolynn Rice)

 New York State Troop E Public Information Officer Mark O’Donnell said that the case is "active and ongoing." Police are doing everything in their power to bring justice to Kristin's family and close the open cold case, he said.

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Now, nearly four decades after Kristin’s homicide, producer Christopher Pavlick is making an investigative documentary series based on the case. The production company Pavlick works for, The Hammer Group, says it has a forensics lab that is certified to analyze evidence by the NYS Department of Health. Evidence includes hair and Kristin's blood-stained clothing.

Pavlick has offered to analyze evidence in O’Connell’s case free of charge, but the NYS Police declined his offer.

Kristin O'Connell's blood-stained clothing (Jolynn Rice)

Kristin O'Connell's blood-stained clothing  (Credit: Jolynn Rice)

Pavlick added that NYS Police agreed to test certain evidence at their Oneida County lab but are now "having trouble trying to figure out where to go" to analyze that evidence, which is what The Hammer Group is offering to do on its own dime.

"They did the testing in that lab, but now they can't figure out what lab is going to do the analysis," Pavlick said. "So … there's all sorts of conversations and stuff trying to figure out where to send it because it’s kind of a two-part process."

Pavlick and O’Connell are calling on the police department to either allow Pavlick's lab to analyze evidence or close the case so they can submit Freedom of Information Act (FOIA) requests to get answers about the case.

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O’Connell has also worked with private investigators and other experts who offered help after hearing about her daughter’s case. She named Noel Hotchkiss, a former high school principal, and Preston Felton, ex-superintendent of the New York State Police-turned private investigator, for offering their assistance in tracking down Kristin’s killer free of charge.

O’Connell is also calling on New York lawmakers to introduce legislation requiring police departments to have units dedicated to solving cold cases rather than handing them from one detective to another throughout the years.