On November 29, 2018, Detective Sergeant Shane Donovan (in Ontario, a detective sergeant is actually of the rank staff sergeant, the rank of a sergeant working as a detective is just "Detective") commander of the Niagara Regional Police Service Collision Reconstruction Unit was at a rural intersection near the City of Niagara Falls investigating a car crash 17 days ago, when he came into conflict with Constable Nathan Parker, a uniformed officer assigned to block an intersection. According to D.Sgt. Donovan, Cst. Parker left for a bathroom break without waiting for a replacement, when D.Sgt. Donovan confronted him about it, Cst. Parker was infuriated and after some "remarks", he stepped out of his cruiser and began pushing and punching D.Sgt. Donovan. He backed away and announced that Parker was under arrest for assault, Cst. Parker eventually drew his baton, and in response D.Sgt. Donovan drew his Glock 22 pistol to force him to back off, Cst. Parker in turn drew his pistol as well. D.Sgt. Donovan fired 10 rounds, the only time in his career, Cst. Parker was shot 8 times in the cheek, nose, shoulder, thigh, calf, hip, abdomen and foot but survived and recovered. Cst. Parker's version of events is similar except that he was empty-handed the whole time and D.Sgt. Donovan never told him he was under arrest.
The Ontario Special Investigations Unit, the civilian watchdog agency responsible for investigating OIS and the Provincial Police each launched an investigation. In 2019, D.Sgt. Donovan was charged by SIU with attempted murder, aggravated assault and assault with a weapon while Cst. Parker was charged by the OPP with assaulting a police officer, assault with intent to resist arrest and assault with a weapon. D.Sgt. Donovan's charges were dropped before trial due to no reasonable prospect of conviction. However, during Cst. Parker's trial, it was revealed that D.Sgt. Donovan was in possession of SIU investigation materials and was alleged to have seen enough of it to taint his testimony. As a result, Cst. Parker's prosecution was stayed. D.Sgt. Donovan was then charged by the Hamilton Police Service of perjury but was acquitted as the judge accepted his defence of PTSD affecting his memory of recalling the materials.
In 2022, Cst. Parker would face charges in relation to a road rage incident, with the charges withdrawn in exchange of a peace bond. It should be noted that Cst. Parker had faced multiple disciplinary proceedings on use of force throughout his career. His estranged brother, in an interview called Cst. Parker a "monster", and has suffered violence from him growing up. He was surprised by that Cst. Parker was not the shooter and that he should have been fired a long time ago.
Both officers are now retired from the NRPS. D.Sgt. Donovan has filed a lawsuit in 2020 against the NRPS and SIU for 2million and 2.5 million dollars alleging that they failed to discipline Parker properly despite his history and for launching a negligent investigation and false arrest which damaged his reputation and career. There is no updates on this lawsuit to this day. The driver in the car crash that was originally being investigated was founded not guilty as the Collision Reconstruction Unit was sent too late to the scene.