Ontario’s chief forensic pathologist took the stand in the Ian Bush murder trial on Wednesday, offering compelling and graphic testimony about the objects allegedly used in the crime.

Bush, 62, is accused of killing retired tax judge Alban Garon, his wife Raymonde and the couple’s neighbour Marie-Claire Beniskos in 2007.

Pollanen testified that Alban Garon seemed to be the primary target of “the most violence.”

The 78-year-old had his hands tied behind his back, and bruises and cuts on his arms and wrists – signs, Pollanen said, of a struggle to survive.

He was found with a plastic bag over his head, kept in place by a “hangman’s noose.” He also suffered severe head injuries, Pollanen said: “Heavy blows to his head ... with force significant enough to fracture his skull.”

The Crown entered a metal bar into evidence, seized at Bush’s home. Asked if that could be the weapon that caused the trauma to Garon’s head, Pollanen said “I could not exclude that.”

He testified that both Raymonde Garon and Beniskos were hog-tied with plastic bags over their heads, consistent with being violently thrown to the floor and suffocated.

But under cross-examination, he clarified that he wasn’t definitively saying that the bar was the object that caused the injury.

The defence also pressed him to pinpoint a time of death, but he said that wasn’t doable from an autopsy; there are far too many variables that can only be determined at the scene.