VANCOUVER -- The British Columbia Appeal Court should consider the finding of a judge who determined in 1983 that a 17-year-old youth accused of murder had the cognitive abilities of a 10- to 12-year-old child, a defence lawyer says.

Thomas Arbogast said the trial judge made that determination after observing Phillip Tallio in court soon after his 22-month-old cousin was killed and hearing audio recordings of a police interrogation.

"The finding was made that he was intellectually impaired and that is something that this court must give deference to," Arbogast said Tuesday.

Court heard that the recordings have gone missing, along with other evidence from the case, and therefore cannot be heard by the panel of three Appeal Court judges now deciding Tallio's fate.

Justice S. David Frankel said the trial judge's finding seemed to be based solely on the conclusion of a registered psychologist who met with Tallio and determined the teen didn't understand the consequences of a plea deal.

Arbogast said that while the judge confirmed the conclusion of the psychologist hired by Tallio's defence team, he made an independent decision about the teen's intellectual abilities.

Several mental health experts have said Tallio did not have the capacity to understand the seriousness of the offence he pleaded guilty to, Arbogast said, adding the teen's "remarkably unusual" behaviour caught the attention of another judge who presided over a preliminary inquiry in Bella Coola in the summer of 1983.

Arbogast read from an affidavit by the judge three decades later after he was contacted by Rachel Barsky, another of Tallio's lawyers.

Arbogast said the judge saw Tallio sitting at the back of a plane alongside a sheriff or RCMP officer as they returned to Vancouver and that the teen was engrossed in comic books his lawyer had brought for him.

"It seemed to me that Phillip Tallio was overwhelmed and he did not comprehend the gravity of his situation," Arbogast read from the affidavit. "I recall discussing this with other members of the court party after arriving in Vancouver."

Frankel said there is no indication the judge had any conversations with Tallio.

"Thirty-three years after the fact he says in an affidavit this is what I recall," he added.

Arbogast replied that the important part of the affidavit is the judge's "very clear recollection" of Tallio's behaviour on the aircraft.

Tallio has said he found Delavina Mack dead in April 1983 when he went to check on her at a home in the northern community of Bella Coola.

He testified last month that he didn't understand what he was signing when he made a plea deal to second-degree murder.

His defence team has said he received "ineffective counsel" from his trial lawyer.

But the CBC reported that Phillip Rankin testified last month that he explained the plea agreement to the teen, who seemed to grasp that he was admitting to killing Mack.

"You can't read other people's minds, what they understand or don't understand, but you get an impression," Rankin said.

"And the impression I had was that he understood what we were talking about."

This report by The Canadian Press was first published Nov. 24, 2020.

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