Nathan O'Brien and his grandparents Kathy and Alvin Liknes are shown in Calgary Police Service handout photos.

Image Credit: THE CANADIAN PRESS/HO-Calgary Police Service MANDATORY CREDIT

CALGARY - The Crown painted a dark picture Monday of the man it believes brutally killed a couple and their five-year-old grandson over a grudge about a patent for an oilfield pump, but the defence urged the jury to use common sense and disputed what it called circumstantial evidence.

"Doug Garland is all about domination," prosecutor Shane Parker said in his closing arguments at Garland's trial. "He neither forgave nor forgot. He stewed."

Garland, 57, is charged with first-degree murder in the disappearance of Alvin and Kathy Liknes and Nathan O'Brien, who was on a sleepover at his grandparents' Calgary home.

Parker said Garland's grudge against Alvin Liknes over the pump they both had worked on was long-standing. He also said the accused fantasized about Kathy Liknes. Court heard during the trial that photos of her were found in Garland's deleted computer files.

The Crown believes the Likneses and Nathan were attacked in the couple's home on June 30, 2014, and that DNA and blood evidence suggests they were still alive when they were taken to Garland's farm north of Calgary.

Parker pointed to the bloody handprint of a child which he said indicated Nathan was bracing himself while walking through the home. He also noted Alvin Liknes's blood trail would suggest he tried to fight off his attacker on the way out.

"They were not going out willingly. They were still alive," Parker said.

The lawyer reminded the jury that closed-circuit security video showed three bodies under a white tarp in the back of a truck like the one Garland drove.

"Nathan, Kathy and Alvin, in these photos are prisoners being held against their will," Parker said.

Parker briefly showed an aerial photo taken on July 1, 2014, that he said showed the diaper-clad bodies of Alvin and Kathy and the smaller body of Nathan lying near a burning barrel.

"This is as close as you get, ladies and gentlemen of the jury, to an autopsy photo for this case. Kathy and Alvin were diapered. This was a very deliberate murder. You can still visualize Nathan curled up near grandma."

Parker told the jury that Garland had researched autopsies and the purchase of autopsy kits. The content of a file labelled "gore" on Garland's computer showed men and women wearing diapers and restrained. It also included pictures of dismembered people.

But Garland's lawyer Kim Ross told the jury said there was no proof Garland was at the Liknes home, no way to identify him as the driver of the truck nor any proof the three victims left the home alive.

"There's not one drop of blood, there's not one strand of hair, there's not one fingerprint, there's not one skin cell. There's no saliva. There's nothing. There's no DNA of Mr. Garland in that residence," Ross said.

Ross said the only conclusion is Garland wasn't responsible for the deaths of the three.

He said there was DNA evidence found at the Garland farm matching the victims but it doesn't prove his client is responsible.

"There's no doubt that there's DNA of these three individuals ... at the farm. But none of these items, ladies and gentlemen of the jury, prove or show that Douglas Garland caused the death of Alvin Liknes, Kathryn Liknes or Nathan O'Brien.

The courtroom was full and included several members of the Liknes and O'Brien families, who issued a public statement.

"The last five weeks have taken a heavy toll on us. It has been unbearable for our family and friends to endure the gruesome details that have been presented throughout the trial," it read.

"We know this has also been hard on the members of the jury and we thank them for their service. Nothing will bring Nathan, Alvin and Kathy back to us, but we can only hope the court will see justice done in their names."

News from © The Canadian Press, 2017