James Landry, 67, is charged with second-degree murder in the death of 43-year-old Philip Boudreau of Petit-de-Grat last year.
Fellow crew member Craig Landry, himself charged as an accessory after the fact, has been detailing his account of events in a Port Hawkesbury courtroom.
The Landrys are third cousins and worked together as deckhands on the fishing boat the Twin Maggies.
The Crown argues a longstanding dispute over fishing territory got out of hand.
The court heard how the crew aboard the Twin Maggies spotted Boudreau out on the water on June 1, 2013. The crew thought he was tampering with their lobster traps and sped toward his small boat.
Craig Landry testified his cousin called for the rifle that was on board. He fired several shots, says Landry, and one of them hit Boudreau in the leg.
Boudreau, who had denied tampering with the traps, pleaded for them to stop saying they broke his leg.
The court then heard how the Twin Maggies rammed Boudreau's boat three times, eventually capsizing it.
Boudreau was left bobbing in the water, clutching a gas can.
Craig Landry said his cousin then told Boudreau, "You won't cut any more of our traps"
According to the witness, James Landry used a gaff to hook Boudreau and begin towing him into deeper water.
Craig Landry, who admitted he had lied early on to police about the whole ordeal, testified he could see Boudreau foaming at the mouth.
He said Landry and the captain of the boat then tied Boudreau's body to an anchor and threw it overboard.
Afterwards, the crew went about its regular fishing business.
Boudreau's body was never found.
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