SKOWHEGAN — A former Industry man found guilty of murder in 2012, when prosecutors used DNA from a cigarette butt to match samples taken from the victim 32 years before, was back in court Tuesday afternoon mounting his third round of appeals on the conviction.

Jay Mercier, 67, through his fourth defense attorney, Amy Fairfield, of Lyman, requested new appeals in the post-conviction review process, including disqualifying the Attorney General’s Office from the case and a motion to allow new DNA analysis.

Superior Court Justice Robert Mullen dismissed the DNA motion based on the fact that the two-year deadline had long since passed for a return to evidence collected from the clothing and body of Rita St. Peter following her murder on July 5, 1980, in Anson.

Assistant Attorney General Lara Nomani told Mullen that the deadline for such a filing expired in December 2014.

Mullen agreed, but Fairfield persisted, telling the court that new technology could enhance the DNA analysis and prove Mercier innocent.

Fairfield said she would present an amended petition for DNA analysis using “new modalities of testing of biological material” that would qualify to be used as evidence under the two-year, post-conviction deadline rule. She said the state has received a grant for new software to study DNA.

“It’s been around for a bit, but just now is coming to Maine,” she said.

Fairfield said there is an alternative suspect in the death of St. Peter, who was 20 years old when she was last seen walking across the bridge over the Kennebec River that connects Madison and Anson late on July 4, 1980. Her bloody and battered body was found the following morning on a field trail off Campground Road in Anson.

Mercier had sexually assaulted St. Peter, beat her with something like a tire iron, then ran her over with his truck, according to prosecutors. Sex assault charges were never brought against Mercier, a point he raises in his request for post-conviction review.

Fairfield said there are two unknown DNA samples and that the new technology could yield results favorable to her client.

Mercier denied killing St. Peter, but DNA evidence taken from St. Peter’s body matched Mercier’s DNA.

Tuesday’s hearing in Somerset County Superior Court was Mercier’s third appeal, and Mullen granted a motion to appoint Fairfield to represent him.

Mercier’s initial appeal was denied by the Maine Supreme Judicial Court in 2014. Another appeal to the U.S. Supreme Court to return the case to the lower court also was denied.

The St. Peter murder was the oldest cold case on the books in Maine until Mercier was arrested in September 2011. Mercier was found guilty in a jury trial in Somerset County Superior Court in September 2012.

Mercier had been a suspect from the beginning, but the case had hit a dead end. In 2005, Maine State Police Detective Bryant Jacques and Maine State Police Crime Lab forensic analyst Alicia Wilcox began investigating the cold case.

When DNA was extracted in 2009 from sperm cells found in biological evidence taken in 1980 from St. Peter’s body, Jacques established contact with Mercier through a series of casual conversations at Mercier’s home, according to Law Court documents from his appeal.

In January 2010, after one of these conversations, Jacques collected a cigarette butt that Mercier had discarded on the side of the road. The DNA obtained from Mercier’s cigarette butt matched that found on St. Peter’s body. Jacques later used the evidence to get a search warrant for a swab of Mercier’s mouth for a more conclusive sample.

Action on a defense motion to preserve evidence in the original case was not necessary Tuesday, Mullen said, because the original order to “keep in place” the evidence is still in effect.

No action has been taken on the motion to disqualify Attorney General’s Office from the case.

Complicating the scheduling of new hearings in the appeal process is gathering witnesses and attorneys involved in the 2012 trial in one place at the same time.

Mercier’s defense attorney John Alsop is a homicide prosecutor with the Attorney General’s Office and his other defense attorney, John Martin, has been appointed as a District Court judge. The prosecuting attorney in the 2012 trial, Andrew Benson, is a District Court judge as well.

Dates were not set Tuesday for new hearings on the appeals, but Mullen said he wants to speed things up.