The Alberta Crown's appeal of the acquittal of a couple in the death of their son is to be heard in June — in a controversial case that has already dragged through two trials and appeals all the way up to the Supreme Court.

David and Collet Stephan were accused of not seeking medical attention sooner for 19-month-old Ezekiel, who died in 2012.

A jury in Lethbridge, Alta., convicted the couple of failing to provide the necessaries of life in 2016.

Although unusual in everyday parlance, the word "necessaries" — not "necessities" — is the term the legal system uses and is, in fact, an actual noun.

The Alberta Court of Appeal upheld the conviction, but the Supreme Court of Canada ruled the original trial judge erred in his instructions to the jury and ordered a second trial.

Back then, the official cause of death was deemed to be bacterial meningitis.

The couple testified they thought their son had croup and used herbal remedies to treat him.

At the second trial, by judge alone, the Stephans were found not guilty in September 2019.

At the second trial, Queen's Bench Justice Terry Clackson sided with a defence expert who said the toddler died of a lack of oxygen, not bacterial meningitis as reported by the original medical examiner.

The Crown contends Clackson committed a number of errors and made comments that gave rise to a reasonable apprehension of bias.

"Simply put, as the Crown continues to drag this case on, we are being provided with the opportunity to further share the truth," David Stephan said Tuesday evening.

The hearing is set for June 11 in Calgary.

"It's the third year in a row that the Crown has celebrated my birthday in court."

'Reasonable apprehension of bias' about judge, Crown says

In his decision, Clackson noted the Nigerian-born medical examiner, Dr. Bamidele Adeagbo, spoke with an accent and was hard to understand.

"His ability to articulate his thoughts in an understandable fashion was severely compromised by: his garbled enunciation; his failure to use appropriate endings for plurals and past tenses; his failure to use the appropriate definite and indefinite articles; his repeated emphasis of the wrong syllables; dropping his Hs; mispronouncing his vowels; and the speed of his responses," Clackson wrote.

David and Collet Stephan smile and hold hands as they leave the courthouse in Lethbridge, Alta., on Sept. 19, 2019, after the judge in a retrial found them not guilty. (Vincent Bonnay/Radio-Canada/CBC)

The judge also called out Adeagbo for "body language and physical antics … not the behaviours usually associated with a rational, impartial professional imparting opinion evidence."

The Crown said in its appeal notice that Clackson took into account "irrelevant considerations."

"The trial judge's comments in the trial gave rise to a reasonable apprehension of bias," the Crown wrote.

Alberta Justice wasting taxpayers' money: Stephan

When asked if he was worried about the upcoming appeal, Stephan said no.

"I am concerned in an attempt to set a precedent that Alberta Justice would use so much of the taxpayers' resources to further injure a family that has already suffered so much loss."

During the second trial, Clackson heard evidence the parents suspected the boy had meningitis and were told days before he stopped breathing to take Ezekiel to a hospital or doctor.

"It's the Stephans' failure to respond to … increasingly alarming information or feedback from their child during that period of time," Crown prosecutor Britta Kristensen said in her closing argument.

"Both parents knew the child had meningitis."

Over the course of the trial, the Stephans testified that they initially thought Ezekiel had croup, an upper airway infection, and they treated him with natural remedies including a smoothie with garlic, onion and horseradish.

They said he appeared to be recovering at times, and they saw no reason to take him to hospital, despite his having a fever and lacking energy.

They called an ambulance when the boy stopped breathing.

Stephan, who was representing himself, said in his final arguments at his second trial that it was paramedics who caused Ezekiel's death by improperly intubating the boy.

A key defence witness, Alberta's former chief medical officer, Dr. Anny Sauvageau, also told court she did not believe Ezekiel actually died from bacterial meningitis.

Sauvageau suggested Ezekiel might have lived had the first ambulance to Cardston, Alta., been better equipped to treat a child his age with breathing difficulties.