The joint submission will come from Hamilton Health Sciences, the hospital that initiated the case, Six Nations and the family of a young girl with cancer, known as J.J. in the media, as well as the province. She can't be identified because of a publication ban.
The provincial Attorney General has been added as a party to "seek clarification" on a court decision from last year, and will appear in a Brantford Court on Friday.
"Since December, Ontario has been working closely with all of the parties in this case," said Brendan Crawley, spokesperson for the Ministry of the Attorney General. The deadline to appeal the rule has been extended three times at the province's request.
Those parties "intend to make a joint submission to Justice Edward when they appearon Friday," Crawley wrote in a statement.
The girl was receiving chemo last September before her mother removed her and took her to Florida for alternative therapy.
That decision prompted McMaster Children's Hospital in Hamilton- a branch of Hamilton Health Sciences, to take the Brant Family and Children's Services to court, seeking to have the child apprehended and placed back into chemotherapy.
A judge dismissed the hospital's application in November, saying traditional aboriginal treatments were in existence before First Nations communities were in contact with Europeans, and were consequently entitled to special protection in Canada.
Ruling celebrated but difficult
At the time of the ruling Six Nations Chief Ava Hill and New Credit First Nations Chief Bryan Laforme welcomed the ruling, saying it has broader effects across Canada.
"This is monumental," said Laforme at the time. "It reaffirms our right to be Indian and to practise our medicines in the traditional way."
Hill said the mother was "overjoyed," with the news.
In contrast, lawyers representing Hamilton Health Sciences, as well as the doctors who treated the girl, left quietly after the verdict.
McMaster Children's Hospital issued a statement a day after the ruling, calling the court case "a difficult circumstance for everyone involved."
"Our motivation has always been and remains that this child receives life-saving medical treatment in a timely manner," the statement reads.
"We have always supported this family's decision to use traditional aboriginal healing practices in conjunction with conventional medical treatment."