Four people are now guilty in the 2019 murder of 25-year-old Nature Duperron.
Buddy Underwood was convicted Friday of second-degree murder, robbery, forcible confinement and kidnapping.
Tyra Muskego was found guilty of manslaughter, robbery and forcible confinement.
Justice R.A. Graesser read both decisions in an Edmonton courtroom.
In September, Kala Bajusz and Grayson Eashappie each pleaded guilty to second-degree murder in the case.
Duperron was kidnapped in Edmonton, robbed, beaten repeatedly in a vehicle, forcibly fed and injected with fentanyl and left to die in the woods near Hinton on April 7, 2019, according to a statement of facts agreed to by Bajusz and Eashappie.
An autopsy concluded that Duperron died from fentanyl and methamphetamine toxicity, and court documents also noted blunt force trauma injuries including to her head.
Graesser described all four convicted, along with Duperron and witness Bret Desjarlais, as a “group of drug intoxicated people driving around with no destination in mind” that night. Desjarlais said they knew each other from the drug trade.
Duperron’s body was recovered from the woods close to Highway 16 near Hinton on April 23, 2019, after Desjarlais took RCMP to her handcuffed body. He was the driver of the vehicle all six people were in, and was later granted immunity for cooperating with police and prosecutors.
The judge found that Muskego was “fully involved” and a “principal actor” in robbing and kidnapping Duperron, but that there was no proof that she participated in the killing, aside from holding the victim down during the drive to Hinton.
The judge ruled that: “Underwood was a party to the killing. He both aided and abetted Eashappie.”
Muskego and Underwood were tried for first-degree murder, but Graesser concluded that the Crown did not prove the “planning and deliberation” necessary for that conviction.
Graesser was not certain that Underwood stating “get rid of her” meant to kill her or that everyone in the truck heard him say those words.
Defence lawyers requested Gladue Reports for both Muskego and Underwood, who are Indigenous. Those assessments can take several weeks to complete. A sentencing hearing has been scheduled for Dec. 2.