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       Constable Nathan Parker, left, and his lawyer, Joseph Markson walk outside Hamilton’s John Sopinka Courthouse. Constable Parker was shot nine times by a sergeant when an altercation broke out during an investigation; Parker is charged with assault.

       Molly Hayes/The Globe and Mail

       A Niagara Regional Police sergeant’s improper access to evidence in an unusual “blue-on-blue” police shooting case has given him an unfair advantage on the witness stand, the defence team representing his colleague has argued.

       Thursday marked Detective Sergeant Shane Donovan’s third day on the witness stand at the trial of his coworker, Constable Nathan Parker.

       Constable Parker, 55, was charged with assaulting a peace officer, assault with a weapon and assault with intent to resist arrest, after he allegedly attacked Det. Sgt. Donovan on a rural road in November 2018. After Constable Parker shoved and punched Det. Sgt. Donovan and then came at him with a baton, the court has heard, the sergeant fired his gun at the constable 10 times.

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       It was originally Det. Sgt. Donovan who was accused in the case. In March 2019, Ontario’s police watchdog, the Special Investigations Unit, charged him with attempted murder, aggravated assault and assault with a weapon. Those charges were withdrawn by the Crown later that year. But the substantial evidence disclosure package that was provided to Det. Sgt. Donovan as an accused person was never collected, and he has had access to it ever since.

       “Sergeant Donovan should never have had possession of the SIU file, from Nov. 23 [2019] on,” defence lawyer Joseph Markson said in court Thursday.

       Niagara police sergeant recalls frantic call for help after shooting colleague in rare ‘blue on blue’ gunfire

       Mr. Markson argued to Justice Anthony Leitch that Det. Sgt. Donovan’s extended access to the files – which included other witnesses’ statements to investigators, as well as crime scene reports – could theoretically have allowed the sergeant to tailor his testimony before the trial of Constable Parker, whose charges were the result of a separate investigation by the Ontario Provincial Police.

       For several hours Thursday, Mr. Markson questioned Det. Sgt. Donovan about specific documents within that disclosure package. Mr. Markson asked, for each item, whether the sergeant had looked at it after his charges were dropped. Over and over again, Det. Sgt. Donovan said he had not.

       Though Det. Sgt. Donovan acknowledged that his memo book notes roughly 40 hours of “case prep” over the last two years, he insisted it was only his own statement to the SIU that he revisited, as well as a few photos. He did not revisit any other witness’s statement after his charges were dropped, he testified.

       The issue of Det. Sgt. Donovan’s custody of the files first came to light in Nov. 2020, when he filed a $2-million civil lawsuit, separate from the current criminal trial, against Constable Parker, the Niagara Regional Police Service and the police services board.

       In Det. Sgt. Donovan’s statement of claim, he alleges that Niagara Police failed to train, supervise, or properly discipline Constable Parker on previous occasions “when they knew or ought to have known he was dangerous and violent.”

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       The lawsuit alleges the service continued to employ Constable Parker “when he was known to have an uncontrollable temper and abuse his authority to harm individuals.”

       Fellow officers were not warned about his temper, the lawsuit alleges, and adequate protections were not put in place for colleagues or the public.

       Det. Sgt. Donovan filed a separate $2.5-million lawsuit against the SIU this past March.

       The court has heard that Nov. 29, 2018 was the first day the two officers had ever worked together, and that their confrontation that day started with a minor dispute.

       Constable Parker, a uniform officer, had been assigned that morning to help block a rural road for a crash investigation. When he at one point left his post unmanned to go for a bathroom break, Det. Sgt. Donovan told the constable he needed to be made aware of such departures. Constable Parker snapped back at the sergeant for not having his radio, and the sergeant reminded the junior officer of his rank.

       Det. Sgt. Donovan recalled his shock that afternoon when the constable got out of his cruiser and shoved him backward. He told Constable Parker he was under arrest for assault, but the officer kept coming at him, he said, throwing “haymaker” punches. Then the constable pulled out his baton. When Det. Sgt. Donovan drew his gun, he said, Constable Parker did the same. The sergeant fired.

       Arguments around the disclosure issue are expected to continue Friday, when the trial resumes.

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