EDMONTON -- Travis Vader's appeal of his life sentence in the deaths of Lyle and Marie McCann was heard in an Edmonton courtroom Tuesday, with his lawyer arguing the term was "demonstrably unfit." 

An Alberta Court of Appeal heard Vader's lawyer state the Crown failed to prove Vader used a firearm in the killings, and so he should not have been sentenced as though he had.

Lawyer Nathan Whitling told the three justice Court of Appeal of Alberta, that the sentencing judge, Justice Denny Thomas, was wrong in sentencing Travis Vader to life sentences for the commission of manslaughter in the 2010 deaths of St. Albert Couple Lyle and Marie McCann.

“In substance, what occurred in this case is Mr. Vader was sentenced on the presumption he killed the McCann’s with a firearm.”  Whitling told the court in arguing that Vader was sentenced for murder, not manslaughter after his 2016 trial.

"It could have occured in any number of ways,"  he said adding "this is just a demonstrably unfit sentence in this case."

Whitling is seeking a sentence in the range of eight to 12 years. 

The McCann's burned-out motorhome and a vehicle they had been towing were later discovered in the bush.

Prosecutor Jason Russell stated that the Crown believes the trial justice did not commit an error in thinking a firearm may have been used.

‘’He applied force to both of them, to not only kill them, but splatter their blood onto possessions in the motorhome," Russell said of Vader's actions.

Russell went on to tell the appeals court that Vader disposed of the bodies and created anguish for the family.

“It cannot be forgotten that he has killed two people.”

The remains of the McCann’s have never been found since their disappearance and deaths.Travis Vader was not present at the appeal hearing.

More than a half dozen family members and friends of the McCann’s listened to the court proceedings but declined comment afterward.

The three appeals justices have reserved their decision until a later date.

Vader could be eligible for parole as early as the spring of 2021 due to credit for his more than four years already served in custody. 

The Supreme Court of Canada refused to hear an appeal of Vader's case on Dec. 5.