James Joseph Landry, 67, has pleaded not guilty to second-degree murder in the disappearance of 43-year-old Philip Boudreau on June 1, 2013.
Landry is among four people charged in the case. All are connected to the Twin Maggies, a lobster boat from the area.
On Thursday, the Supreme Court in Port Hawkesbury heard details of the last day Boudreau was seen alive.
“This case is about murder for lobster," prosecutor Steve Drake argued. "It's not about a loss of control. The crew of the Twin Maggies carried out a sustained attack."
Boudreau's overturned boat, a skiff, was found in the Petit-de-Grat harbour, but his body has never been recovered.
Prosecutors told court the crew shot at Boudreau four times, ran over his boat several times and then tied his body to an anchor, which was dropped overboard.
The Crown did not elaborate on Thursday on how the killing may have been tied to lobster.
According to an agreed statement of facts read into the court record, a bullet recovered from Boudreau's boat came from a gun that was later found at the D'Escousse home of Dwayne and Carla Samson.
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