09/15/2016 08:20 EDT

Travis Vader Guilty Of Second-Degree Murder

Lyle and Marie McCann vanished six years ago.

EDMONTON — The son of an Alberta couple who disappeared from a campground in Alberta bush country more than six years ago said Thursday that a murder verdict in their deaths is a huge relief to the family.

But while the agonizing wait for the judge's decision is over, questions about how Lyle and Marie McCann died remain.

"We don't know exactly what happened on that afternoon ... and probably never will," Bret McCann said outside court after Travis Vader was found guilty of second-degree murder.

"The convicted person will need to talk and we're not optimistic that will happen.

Travis Vader arrives at court in Edmonton on March 8, 2016. (Photo: Amber Bracken/Canadian Press)

"I have to stand down. I'm sorry, mum and dad, I can do no more. I hope that some day, somehow you will be found. I take joy in the legacy you have left behind.

"Our memory of you will last forever."

Justice Denny Thomas said there was no reasonable doubt that Vader killed the McCanns during a robbery, but there was nothing to suggest he intended to do so.

"I cannot conclude beyond a reasonable doubt that Mr. Vader killed the McCanns in a planned and deliberate manner," Thomas said in a decision that was broadcast live from an Edmonton courtroom.

"Our memory of you will last forever."

"The killing of the McCanns was not a first-degree murder. It is therefore a second-degree murder."

Thomas also rejected a Crown scenario in which Vader killed one of the McCanns during the robbery and then killed the other to eliminate a witness. The justice said there were other possibilities as to how the McCanns died.

The conviction carries an automatic life sentence, but a hearing still needs to be held to determine Vader's parole eligibility. Thomas said he would set a date for that hearing on Oct. 3. Court will also decide on that day whether Vader should be given a psychiatric assessment.

The portrait of Lyle and Marie McCann sits at their memorial service in 2011. (Photo: The Canadian Press)

The bodies of the McCanns, who were both in their late 70s, have never been found, but Vader's DNA and a fingerprint were found in their SUV. The vehicle and the couple's burned-out motor home were discovered west of Edmonton days after the McCanns vanished.

Thomas said Vader's motivation when he came upon the couple at a campground was to rob them because he was broke, hungry and a drug addict.

"The McCanns and their property were likely nothing more than a target of opportunity — an opportunity that Mr. Vader took."

Vader to appeal verdict

Vader's lawyer, Brian Beresh, said his client will appeal the verdict.

Beresh said the judge appears to have constructed his own version of what happened based on circumstantial evidence.

"We want to review the decision," Beresh said. "There will be an appeal based upon what we think are errors in the judgment."

The Crown had argued that Vader, 44, was a crystal meth user living in a makeshift camp when he came across the McCanns and killed them.

The defence countered that, without evidence of human remains or a murder weapon, the Crown's case was little more than a collection of theories and circumstantial evidence — and that there was no proof the couple was even dead.

"There was bloodshed. A gun was discharged."

Thomas dismissed the idea the McCanns could still be alive.

"Violence occurred in the interaction between the McCanns and Mr. Vader. There was bloodshed. A gun was discharged," he said.

"The McCanns were victims of violence. Mr Vader inflicted that violence. The McCanns suffered bodily harm. The presence of their blood makes that obvious."

We were 'robbed of this happiness': McCanns

Their son said his parents were kindred spirits, who were married in 1952, loved being together and had a happy life that ended too early.

"It is so, so sad that my parents didn't live to fully enjoy their golden years, did not live to enjoy their great-grandchildren. They and us were robbed of this happiness."

The prosecution called forensic evidence suggesting Vader's DNA or fingerprints were found on several items key to the case, including a can of Boxer beer found in the SUV the McCanns had been towing, though the defence argued that only proved Vader had "incidental contact" with the vehicle.

Nicole Walshe, daughter of Bret McCann, Bret McCann and his wife Mary-Ann McCann speak to media, Sept. 15, 2016. (Photo: Jason Franson/The Canadian Press)

Beresh had allowed it might be possible Vader stole the vehicle, but that didn't mean he killed anyone.

The trial was also told a ball cap found in the SUV had both Vader's DNA and Lyle McCann's blood on it, while blood from Marie McCann was found on canned goods in the back of the vehicle.

Beresh countered that sneezing into a vehicle or onto items might be enough to transfer DNA.

The defence suggested a friend of Vader's who died five years ago might have killed the McCanns.

On Thursday, the guilty verdict appeared to be enough after what Bret McCann called the marathon of the last six years.

"We're thrilled that justice has been served," he said.

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