Fourteen members of an Australian religious group have been convicted of killing an eight-year-old diabetic girl who was denied insulin for almost a week.

Elizabeth Struhs died at home in 2022 from diabetic ketoacidosis, which causes a dangerous build-up of ketones – a type of acid – and blood sugar spikes.

The court heard that Elizabeth’s treatment was withheld because the group, known as the Saints, opposed medical care, believing God would heal her.

Her father Jason Struhs and the group’s leader Brendan Stevens were on trial for murder but convicted of the lesser charge of manslaughter. Twelve other members, including Elizabeth’s mother and brother, were also convicted of manslaughter. All had pleaded not guilty.

When handing down his almost 500-page verdict on Wednesday, Justice Martin Burns said that although it was clear Elizabeth’s parents and “every member of the church including all other accused” had adored her, their actions had resulted in her death.

“It cannot be doubted that Elizabeth was lovingly cared for in almost every way,” he said.

“However, due to a singular belief in the healing power of God… she was deprived of the one thing that would most definitely have kept her alive.”

The Saints are not affiliated with an established church in Australia and have roughly two dozen members from three families.

The judge-alone trial in the Supreme Court of Queensland began in July last year and lasted several months.

Prosecutors called 60 witnesses and painted a picture of an “intelligent” child who suffered greatly in her final days.

“She was described as speaking little, needing help going to the toilet, and being incontinent,” prosecutor Caroline Marco said, adding that the girl would have endured vomiting, extreme lethargy, and a loss of consciousness.

The congregation, meanwhile, had prayed and sung for Elizabeth, whose health deteriorated as she lay on a mattress at her home in Toowoomba, about 125km (78 miles) west of Brisbane.

No effort was made to call a doctor, and authorities were not notified until 36 hours after her death, as the group believed she could be brought back to life, the court heard.

The 14 defendants, aged between 22 and 67, represented themselves at trial, having all refused legal representation or to enter pleas. The court was required to enter not guilty pleas on their behalf.

Most had been charged because they had either counselled or aided her father in his decision to withhold Elizabeth’s insulin, the court heard.

Prosecutors said that Jason Struhs, 53, had converted to the church much later than his wife Kerrie Struhs, 49, and that he had previously supported giving Elizabeth medicine.

They argued he changed his mind after being baptised into the group and that ultimately he knew the decision would end his daughter’s life.

Speaking through tears when it was his turn to take the stand at trial, Jason Struhs said that he and Elizabeth had agreed to “stop the insulin” together, and that he still believed his daughter would be resurrected.

“Elizabeth is only sleeping, and I will see her again,” he told the court.

Stevens, 63, defended the group’s actions as faith-based and described the trial as an act of “religious persecution”.

He said that the group was within its “rights to believe in the word of God completely” and that their decision not to enter pleas was because the congregation had “no intention of fighting” the case by using law.

Elizabeth’s sister Jayde Struhs told the trial she had left the Saints and fled her family home at 16, after coming out as gay, and was now estranged from them.

She and other witnesses described the congregation as having increasingly strict views, including that mainstream healthcare should be shunned and that both Christmas and Easter were “pagan” or ungodly festivals.

The court also heard that Elizabeth’s life had been in danger in 2019 when she was admitted to hospital in a diabetic coma weighing just 15kg (2st 5lb), after having become too weak to walk.

She was then diagnosed with type 1 diabetes, and her family was told she would need daily insulin injections.

Both parents were charged over that incident – however Jason Struhs testified against his wife and received a more lenient sentence.

At the time, he said his wife – who had been a member of the Saints for years – did not believe in providing their kids with medical treatment for religious reasons. He also openly expressed regret for having “let his daughter down”.

The court heard he later helped provide her with insulin for a period while his wife was in jail, but that he then faced pressure from other members of the religious group to stop doing so.

Giving his verdict, Justice Burns said that Jason Struhs and Stevens couldn’t be convicted of murder because prosecutors had not proved beyond a reasonable doubt that the pair had intended to kill or cause grievous bodily harm to Elizabeth.

But all 14 defendants were guilty of manslaughter, he ruled, because they were jointly involved in a crime that resulted in her death.

Jayde Struhs said that while she was pleased with the verdict, the “system had failed” her sister.

“We are only here today because more wasn’t done sooner to protect her or remove her from an incredibly unsafe situation in her own home,” she said in a statement outside court.

The group is expected to be sentenced next month.

Toowoomba has long had a “colourful array of sectarian Christian groups and independent churches of various kinds”, says Bernard Doherty, who studies new religious movements.

“The Saints appear to be one of these small independent churches which form around a few families,” he told the BBC, adding that little is known about the close-knit congregation.

Jayde Struhs said the Saints had attended the Revival Centres International church in Brisbane, but they broke away after Stevens failed to become a pastor there. They then formed their own parish and held sermons at his house multiple times a week, she said.