After driving a pickup truck over his boyfriend's head, Jody Shane Wright held Troy Young and cried, a Calgary court has heard.

Young's face was collapsed and Wright believed his on-again, off-again boyfriend was dead. 

It was April 29, 2014 and the pair were drunk and high on crystal meth.

Wright had been chasing Young — who was on foot — with the truck. He accidentally ran the 23-year-old over.

Wright panicked, according to an agreed statement of facts read before Court of Queen's Bench Justice Robert Hall, who accepted a guilty plea to manslaughter on Monday.

Troy Young

Troy Young was killed in April 2014 after his boyfriend drove over him in a pickup truck during an argument. (Evan J Strong Funeral Services)

Wright tied Young's body to the back of the Ford F250 with an extension cord and dragged the dying man to a wooded area about two kilometres from the home the two men shared on the Siksika First Nation.

The next day, Wright called RCMP to report his crime, leading officers to Young's body.

Originally charged with second-degree murder, Wright, 43, pleaded guilty to manslaughter, as arranged by prosecutors Doug Simpson, Dane Rolfe and defence lawyer Gloria Froese.

Wright co-operated with police from the get-go. He told investigators that he and Young had been in the truck outside their house when they got into a fight. Wright was punched in the face by Young, who then went inside the home to pick up a phone charger. 

When he came back outside, Wright began chasing his partner in the truck, driving in a "zigzag pattern" around the yard, through a field, in a ditch.

Young was throwing things at the truck and hitting it when it would get close.

Wright felt two bumps

Wright then drove at his boyfriend to "scare him" but he ran over Young, crushing his skull and fracturing his spine, according to a forensic pathologist who examined the body.

After he felt two bumps, Wright said he stopped and saw Young lying on the ground behind the truck.

That's when he got out and held Young, believing he was dead.

The pathologist determined that Young was still alive when he was being dragged, but wouldn't have survived much longer.

Pre-sentence reports have been ordered and Wright will be sentenced later this year.