A Calgary couple found guilty two years ago of killing their diabetic teenage son have lost their appeals to have their convictions overturned.

Emil and Rodica Radita were challenging their first-degree murder convictions in the 2013 death of 15-year-old Alexandru.

Both their appeals were dismissed.

The three-judge panel of the Alberta Court of Appeal issued the decision Thursday morning, writing that they have rejected all three grounds of appeal filed on behalf of Emil and Rodica Radita.

In 2017, Court of Queen's Bench Justice Karen Horner convicted the Raditas and sentenced them to life in prison with no chance of parole for 25 years.

The Raditas filed separate notices of appeal the following month.

"The appellants have not demonstrated any reviewable errors in the trial judge's analysis of intent," says the decision from Justice Patricia Rowbotham, Justice Barbara Lea Veldhuis and Justice Dawn Pentelechuk.

The three appeal court judges went on to dismiss the appellants' claim that Justice Horner's analysis under section 231 (5)(e) of the Criminal Code — which elevates second-degree murder to first — was flawed.

The appellants also argued that the judge showed bias by crying during the trial.

"I am not guilty of murdering my son, and the judge finding that I am shows that she did not look at all of the evidence," Rodica​ Radita said in a handwritten note when she filed her appeal.

The Court of Appeal ruling dismissed this argument, saying there are no grounds to believe the trial judge failed to conduct a dispassionate investigation of the facts.

"An informed person, viewing the matter realistically and practically, and having thought the matter through, would not conclude that the trial was unfair," the decision says.

Witnesses at their trial testified the boy was so neglected that he weighed 37 pounds and was covered in 44 ulcers and wounds when he died in 2013 of complications from untreated diabetes and starvation.

When Horner handed down her verdict, she said the couple was in gross denial of Alex's disease.

"Children in Canada rarely die from diabetes, but proper treatment requires due diligence," the trial judge said.

Horner said it appeared that Alexandru had not received proper care for years, even though the Raditas were fully trained in how to look after him.

Witnesses testified during the trial that the boy would have suffered immensely leading up to his death.

The Raditas had a long history of refusing to properly treat Alexandru's condition. Alex nearly died when he was five and was seized from his parents until a judge in British Columbia returned the boy to his family.

Around 2009, the family moved to Alberta, where Alex was never taken to see a doctor and never attended school.

When paramedics were called to the Radita home in May 2013, they found Alex's near-skeletal body on his bed. He was so badly emaciated, the medical examiner testified the boy was in the 0.1 percentile for 15-year-olds based on his weight and height.

Calgary criminal defence law expert Andre Ouelette says the Court of Appeal agreed with the trial judge's conclusion that the actions of the parents in mismanaging his medical situation went beyond recklessness — the benchmark for a lesser conviction of manslaughter.

"And together with the fact there was almost a form of confinement in his room, that amounted to an imputed intention," he said. "And on that basis, I think, the judge analyzed it, convicted them [of first-degree murder] and the Court of Appeal of Alberta agreed with that."

The appellants can now make an application to appeal to the Supreme Court of Canada, but since the Alberta Court of Appeal decision was unanimous, they have no automatic right to be heard by Canada's top court, he said.

"I think, likely, this may be the end of the road," he said.