The trial continues Friday for an Industry man accused of killing a woman more than three decades ago. Jay Mercier, 56, was arrested last September for the murder of Rita St. Peter, 20. Her body was found along a road in Anson in July of 1980. Friday, Kathleen Shagnon testified that she knew Mercier and St. Peter. Shagnon lives in Maryland now, but lived in Madison in July of 1980. Shagnon said she was at the Depot Bar on Main Street in Madison the night St. Peter was killed. She said she saw a very drunk St. Peter walking south on Main Street. Shagnon said St. Peter was so drunk that she saw her fall down. Shagnon said she watched Jay Mercier walk out of the Depot Bar, get in his truck, and start heading north before making a ” tire-squealing, emphatic U-turn” and head south in Rita St. Peter’s direction. Police have never found a murder weapon. Deputy Attorney General Andrew Benson said modern forensics led them to charge Mercier, saying bodily fluids taken from the victim and tire impressions left at the scene, languished in an evidence locker for three decades. In 2010, authorities were able to create a DNA profile from that evidence. Police got a sample of Mercier’s DNA from a cigarette butt he dropped on the ground while being interviewed by police. Using that sample, police were able to obtain a warrant to swab Mercier’s cheek for a complete DNA profile, which they say matches the one created from the 1980 swabs. The defense argues that Mercier is being charged using the same evidence police have had from the beginning.” The fact that they now know Jay Mercier slept with Rita St. Peter and he lied about it, that’s what’s changed. But that’s not murder ladies and gentlemen. They’ve had the same evidence for 32 years and they couldn’t bring in Jay Mercier,” said John Martin, defense attorney. The man who discovered St. Peter’s body in 1980 testified on Thursday, as did some of the law enforcement officers who worked the case.