AUBURN – Jury selection is expected to start Monday in the trial of a Sabattus man charged with murder in the shooting death of his father.

Scott Poirier, 35, admitted killing his father during Roland “Jerry” Poirier’s 65th birthday party in 2006, police said.

The younger Poirier claimed his father had sexually abused him when he was younger and feared the man might abuse his son’s four children. He is being held without bail at Androscoggin County Jail.

The trial is scheduled to last a week and a half, a court clerk said.

Poirier is expected to assert an affirmative psychiatric defense, seeking to prove he wasn’t criminally responsible for his father’s death. He was ordered by an Androscoggin County Superior Court judge to undergo psychological evaluations in December 2006 at the request of state prosecutors. The results of those evaluations have remained sealed.

A psychologist is expected to testify as a defense witness during the trial. Prosecutors had expressed concern about aspects of that expert’s testimony the jury might hear. Justice Joyce Wheeler, who is expected to preside over the trial, said she would decide whether to limit that expert’s testimony and to what extent once the trial is under way next week, a court clerk said.

Police said Roland Poirier was celebrating his birthday the night of Nov. 8, 2005 in the dining room of his Grove Street home in Lewiston with more than a dozen family and friends. He was shot in the back of the neck by Scott Poirier, who was standing outside in the yard during heavy rain, police said. He fired a .270-caliber rifle through a sliding glass door, shattering a wine bottle. Roland Poirier died at the scene, according to police.

Scott Poirier was quoted by police as telling a relative during a telephone call shortly before the shooting that, “Lies will end tonight.” His roommate told police Poirier had become emotionally distraught shortly before the shooting, punching holes in the walls of his Davis Lane home.

The trial was postponed from its September date after Poirier’s attorney and the trial judge were appointed by Gov. John Baldacci to new judicial posts.

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