Jay Mercier of Industry was convicted in 2012 of killing Rita St. Peter in 1980.

A Maine man convicted in 2012 of what was at the time the oldest cold case killing in the state has returned to court for an appeal.

Jay Mercier, 63, was found guilty of murder stemming from the 1980 death of Rita St. Peter in Anson. Prosecutors used DNA from a cigarette butt to match samples taken from St. Peter.

Mercier’s lawyer, Amy Fairfield, requested new appeals in the post-conviction review process in October. Fairfield has told the court new technology could prove Mercier innocent.

The Morning Sentinel reports the case was in court Monday. Fairfield has said there’s an alternative suspect in the case.

St. Peter was last seen walking across a bridge over the Kennebec River that connects Madison and Anson. Her body was found the next morning.