SKOWHEGAN — State Police Sgt. AJ Carter had a Polaroid instant camera with him July 5, 1980, when Rita St. Peter’s body was found off Campground Road in Anson.

Carter, who retired in 1996, snapped a photo of tire marks in the mud near where St. Peter’s body was found, partially clad and bloody.

Prosecutors in Somerset County Superior Court want to link prints of tires photographed by police that day to ink prints taken the following day of tires from a truck owned by 57-year-old Jay Mercier of Industry who is on trial, charged with murdering St. Peter.

Moments after Carter shot the picture of the tire marks in a mud puddle near the crime scene, Somerset County Sheriff William Wright, ignoring the pleas of a game warden stationed to preserve the scene, ran his vehicle through the area and destroyed the best of the tire marks, Carter and former game warden James Ross testified on Thursday.

Police were able to photograph some impressions later, but the best ones were destroyed, according to the two men.

The problem Thursday, the first day of the trial, a day the state was trying to use the tire comparisons as evidence to place Mercier at the crime scene, was the fact that Carter’s photograph, which was never catalogued as evidence, is gone.

“It was burned,” Carter said of the Polaroid photo.

He said he burned it in a camp fire near his home several years ago when he got rid of many of his old files and reports. It had never been turned over to the primary investigator in the case, Carter said, because he considered it his own investigative tool to compare tires on other possible suspect vehicles and not evidence in a murder trial.

The day after he took the picture, on July 6, Carter used an ink roller to make paper prints of tires on Mercier’s truck. Mercier was already a suspect and police got written permission that day from him to examine his truck.

Carter said the tires he took a picture of looked similar to the tires on Mercier’s Red 1980 GMC pickup truck. They were distinctive snow or mud tires, Ross, the warden who had tried to protect the crime scene, testified earlier on Thursday.

The ink prints were turned over to the state police crime lab in Augusta and were on display in the courtroom, but the rim size, tire size, type and brand of the ones on Mercier’s truck had not been noted at the time.

Attorney John Alsop, one of two lawyers representing Mercier, asked Carter if the prints of the tires had been compared to the marks left at the crime scene.

They were not, Carter replied.

“That would be a significant fact, wouldn’t it?” Alsop said.

Carter agreed, saying he was fourth in command that day and the investigation was being handled by other members of state Police Criminal Investigation Division in Augusta.

It wasn’t until December 2005 that a forensic scientist matched the tire impressions to those from the crime scene, according to court documents. Alsop previously has said that he wants to know why the tire impression evidence was not completed until 25 years after the crime, but that question has not yet been raised at trial.

St. Peter, 20, was last seen alive around midnight July 4, 1980, near the bridge connecting Madison and Anson. She had been at a Fourth of July party and stopped at the Depot Tavern in Madison for a nightcap.

Two people told police they saw Mercier in his truck outside the bar around the same time.

Mercier is accused of sexually assaulting St. Peter, beating her to death with something similar to a tire iron and then driving over her body with his pickup truck. He has pleaded not guilty.

Assistant Attorney General Andrew Benson said semen taken from St. Peter’s body was stored as evidence for 25 years, before modern forensic investigation procedures could identify DNA. Mercier’s DNA later was matched to that found with St. Peter from samples taken by state police. The trial continues at 8:15 a.m. today

Doug Harlow — 612-2367

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