INDUSTRY – A 55-year-old man was arrested Wednesday and charged with murder in the unsolved killing of a woman whose battered body was found 31 years ago in Anson, the Maine Attorney General’s Office said.

Jay Stephen Mercier was arrested at his home at 5 Butterfield Lane in Industry at about 8:30 a.m. He was taken to the Somerset County Jail, where he is awaiting his first court appearance, said Assistant Attorney General Andrew Benson.

Investigators had a recent breakthrough using forensic evidence from the long-unsolved homicide of Rita St. Peter of Anson, who was 20 at the time she was killed, Benson said. A Somerset County grand jury indicted Mercier on the murder charge Sept. 16.

Law enforcement agencies spent three decades interviewing hundreds of people and reviewing evidence in the case, Benson said.

He declined to say what forensic evidence was reviewed recently at the Maine State Police crime lab. A Department of Public Safety news release said the evidence led to the breakthrough in the case.

St. Peter’s body was found off Campground Road in Anson on July 5, 1980. She had been beaten, her skull was fractured and police said she may have been run over by a car or a truck.

Autopsy results, the cause of her death and other details of the case have been withheld from the public and family members, according to past interviews with relatives and police.

Benson said Wednesday that he can’t say why the information was withheld or discuss other details of the investigation or the arrest of Mercier, who will face 25 years to life in prison if he is convicted of the murder charge.

St. Peter was last seen walking after midnight on July 4, 1980, crossing the bridge from Madison to Anson. She had been seen drinking that night at a bar in Madison. She was living with her parents in Anson and worked at Ken’s Family Drive-In, a restaurant in Skowhegan.

St. Peter had a daughter who was 3 at the time of the killing.

Anson residents expressed relief at the news of the arrest Wednesday.

St. Peter was in Paul Thompson’s biology class during her sophomore year at Carrabec High School in North Anson.

“A real nice kid. Quiet. Good student,” said Thompson, who still teaches at the school. Her death “really did shake the community.”

At Carrabec High, St. Peter was treasurer of her junior class and participated in Future Homemakers of America, according to her 1978 senior yearbook.

Lisa Turner of Anson, who graduated from Carrabec four years after St. Peter, said people have wondered about the case for the past three decades.

“I’m glad it’s over, that they’ve come to a decision,” she said.

Tom Baker bought property on Campground Road in 1995. Though he acknowledged that Mercier has only been arrested, and not convicted, he said, “What goes around comes around, at least we can always hope.”

Another Anson resident, Kathy Stevens, said she lived in neighboring Madison at the time of St. Peter’s death and was never in fear. “I wanted it to be solved for the family,” she said.

Mercier is divorced, has been employed as a laborer most his life and was living with his girlfriend at the time of his arrest, according to the news release. Benson didn’t know the girlfriend’s name and referred questions about Mercier’s past to other law enforcement agencies.

Somerset County District Attorney Evert Fowle said his office’s records show that Mercier had several convictions on his criminal record as of 2008. He lived in Madison before moving to Industry around 2008, Fowle said.

Mercier was convicted of two assault charges in 2003, two drunken-driving charges around the same time and several other traffic violations, Fowle said.

In 2009, Mercier admitted to a civil charge of cruelty to three horses, which he owned while living in Industry, said Franklin County Assistant District Attorney Andrew Robinson.

Mercier’s court documents remained sealed Wednesday morning in Somerset County Superior Court, even after Mercier had been booked at the jail and his name had been released. A clerk said the judge’s order impounding the documents also was sealed.

Around noon, Mercier’s indictment was made public. It does not reveal the specific cause of St. Peter’s death, alleging only that Mercier “did intentionally or knowingly cause the death of Rita St. Peter, or engaged in conduct that manifested a depraved indifference to the value of human life and which in fact caused the death of Rita St. Peter.”

An indictment is a finding by the grand jury that there is enough evidence to charge a person with a crime.

Mercier is scheduled to have a video arraignment at 1:30 p.m. Friday in Somerset County District Court, said John Alsop, a Skowhegan-based attorney who was consulted by the court Wednesday as a potential defense attorney for the case.

Justice John Nivison has been assigned the case, according to court documents. 

Morning Sentinel Staff Writer David Robinson can be contacted at 861-9287 or at:

[email protected] 

Morning Sentinel Staff Writer Erin Rhoda can be contacted at 612-2368 or at:

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