Mayerthorpe tragedy
gun shot murder of 4 police officers and suicide
The Mayerthorpe tragedy was a fatal shooting that occurred on March 3, 2005, on the farm of James Roszko, approximately 11 km (6.8 mi) north of Rochfort Bridge near the town of Mayerthorpe in the Canadian province of Alberta.
Roszko shot and killed four Royal Canadian Mounted Police (RCMP) constables: Anthony Gordon, Lionide "Leo" Johnston, Brock Myrol and Peter Schiemann. He then committed suicide. The attack occurred as the officers were executing a search warrant for stolen property and a marijuana-growing operation on the farm. Two individuals who were not present at the shooting, Shawn Hennessey and Dennis Cheeseman, pled guilty to manslaughter for assisting Roszko to return to his farm.
The incident was the worst one-day loss of life for the RCMP since five officers drowned on June 7, 1958, and the worst multiple-officer killing in contemporary Canadian history.
Incidents
Initial contact with Roszko
On the afternoon of March 2, 2005, two civil bailiffs went to the farm owned by James Roszko to repossess a truck he had purchased, but not made any payments on. The bailiffs arrived around 3:00 pm. There was a metal gate blocking the road into the farmyard. When Roszko saw the bailiffs, he released two large aggressive Rottweilers.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Jun 30, 2026. The linked authority identifier is Q6797090. Authority coordinates are 54.015, -115.022. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 2005 and 1958.
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