Gun could fire even if trigger not pulled, expert says in OPP officer's manslaughter trial

There are ways a hand gun could fire without an officer pulling the trigger: That was the expert testimony of a witness for the defence in the manslaughter trial of OPP Const. Sean O'Rourke on Tuesday. 

Christopher Butler was qualified as a expert witness with years of experience as a trainer and use of force reviewer with the Calgary Police Service. He has given expert testimony in more than 30 cases. 

He was called to testify for the defence for O'Rourke, who is on trial in the shooting of 24-year-old Nicholas Grieves, who died after stealing $40 of gas from a Dutton gas station in July 2021. 

Much of Butler's testimony revolved around police use of force and firearms — including instances where Glock hand guns, like the one O'Rourke had, have gone off without the officer pulling the trigger.

Butler told the court it had happened to him, and that subsequent examination showed microscopic cracks in the gun. 

In another similar instance, a tactical officer with the Calgary Police Service had a Glock hand gun in a holster on his leg when it went off after a slight impact during a high-risk vehicle stop.  Those results were able to be replicated, and also showed microscopic defects in the interior of the gun, Butler testified. Butler cited a third example in Winnipeg. 

These incidents tend to happen in "high mileage" guns that have fired many rounds and have been found, upon further inspection, to have microscopic defects, Butler said. 

But the defence and Crown questioned Butler about police use of force and his opinion on whether O'Rourke's actions — how he approached the car and the positioning of his weapon as he did so — were appropriate.

Butler said he felt O'Rourke's actions were appropriate in the situation, citing research about the risks officers face while doing traffic enforcement work, the lack of compliance by the car's occupants with O'Rourke's instructions and his close proximity to the car. 

On cross-examination, Crown attorney Jason Nicol pointed to other pieces of testimony, and tried to establish that the gun only would have fired because O'Rourke pulled the trigger — with which Butler disagreed. 

On Friday, the Crown cross-examined O'Rourke, suggesting the theory that he tripped and fell into the suspect vehicle carrying Grieves and two others was a lie to cover up his own "carelessness."

Court will continue on Friday with closing arguments.