The main issues at the RCMP's Labour Code trial over the 2014 shooting deaths of three Moncton Mounties and wounding of two others are carbine weapons and training, defence lawyer Ian Carter reminded the Moncton courtroom during his opening statement on Friday.

The RCMP is not charged with causing the deaths of its members, stressed Carter. It was Justin Bourque who went on a shooting rampage in a residential area of the city's north end on June 4, 2014, he said.

The national police force needed to carefully study carbines before arming its officers with the semi-automatic weapons that are made to be lethal, said Carter.

Not all carbines are the same, he said, citing the different barrel lengths and ammunition as examples. And it can be difficult to purchase weapons and accessories, with many parts coming from the United States, he said.

During closing arguments, the defence will provide a timeline of the development of the carbine rollout, said Carter

The defence also intends to prove the RCMP's training program was of high quality, he said.

rcmp shooting barricade

No carbines were available to the Moncton Mounties who responded to Justin Bourque's shooting rampage on June 4, 2014, the Labour Code trial has heard. (Marc Grandmaison/Canadian Press)

The RCMP is charged with violating four provisions of the Labour Code by allegedly failing to provide members with appropriate use-of-force equipment and training for responding to an active threat or active shooting event, and failing to ensure the health and safety of every person employed by the force.​​

Each of the four charges carries a maximum fine of $1 million. No individual RCMP manager or supervisor is named in the charges.

The Crown called its last witness in the case Wednesday.

The trial started on April 24. Two months have been set aside.

Bourque was armed with an M305.308 semi-automatic rifle and a Mossberg 500 12-gauge shotgun when he fatally shot constables Douglas Larche, Dave Ross, and Fabrice Gevaudan, and wounded constables Darlene Goguen and Eric Dubois.

The responding officers were equipped only with pistols and shotguns. No carbines were available to them that night, the trial has heard.

Carbines are high-powered, short-barrelled rifles that have a longer and more accurate range than a pistol or shotgun.

Bourque is serving five life sentences with no chance of parole for 75 years after pleading guilty to three counts of first-degree murder and two counts of attempted murder.

With files from Tori Weldon