Elva Bottineau was granted standing at the coroner's inquest probing the death of five-year-old Jeffrey Baldwin, who died 11 years ago while in her care.
In his decision, coroner Peter Clark said standing must be given to anyone with a "direct and substantial interest" in a particular inquest.
"While the concept of Ms. Bottineau's participation at this juncture may be painful, I am bound to consider each application on its own merits, in a dispassionate and objective manner and with due consideration for the principles of fairness and natural justice," he wrote in the ruling.
"It may be that Ms. Bottineau has useful information to assist the jury, whether by testimony, questioning of witnesses or submission."
A lawyer presenting her application has argued Bottineau — as Jeffrey's caregiver and relative — has unique insights that could help the jury make its recommendations.
But the request was strongly opposed by lawyers representing the boy's surviving siblings and the office of Ontario's advocate for children and youth.
They said allowing her to take part in the proceedings would grant her a soapbox to defend her actions and revisit her conviction.
Lawyers also questioned Bottineau's ability to follow instructions, given her "limited intelligence."
Clark addressed those concerns in his decision, saying Bottineau's involvement in the proceedings would be subject to some restrictions.
"Such limits may include, but are not limited to, which witnesses she may cross-examine and the nature of such cross-examination," he wrote.
She will not be allowed to recall past witnesses and, should she wish to present or call evidence, she will give a statement to be reviewed by the coroner, he said.
A video or telephone link will be set up so Bottineau can listen to the inquest without appearing in person, which would require moving the proceedings to a secure venue.
"Ms. Bottineau has been convicted of a serious and reprehensible crime and for her own safety and the safety of those in attendance, it would not be prudent to allow her to attend the hearing in this building," Clark wrote.
"Should Ms. Bottineau satisfy me that she has relevant and admissible evidence to provide to the jury, I will then consider whether arrangements should be made to have her appear in person at a secure facility or whether such testimony could be heard via video link."
It isn't the first time the person responsible for a death has taken part in the related inquest.
A teen girl who pleaded guilty to second-degree murder in the death of three-year-old Matthew Reid was also granted standing in that 2010 inquest.
Bottineau and her partner Norman Kidman are serving life sentences for second-degree murder in the case.
The inquest has heard that both had a history of child abuse, including separate convictions and various dealings with the children's aid society, something children's aid workers only discovered after Jeffrey's death.
Jeffrey was so severely starved at the end of his life that he couldn't lift his own head.
The Toronto Police Service also made a successful bid for standing Wednesday.
The force will present evidence on record checks performed for the York Children's Aid Society as well as the sharing of information between authorities, its lawyer said.