TORONTO -- Police reports on domestic incidents involving a couple convicted of killing a seven-year-old Toronto girl in their care should be entered as evidence in the coroner's inquest into the child's death, according to Ontario's advocate for children.

A notice of motion filed by the Provincial Advocate for Children and Youth argues the reports provide crucial information that will help understand the circumstances that led to Katelynn Sampson's death in 2008.

The motion relates to eight reports on domestic incidents during Donna Irving and Warren Johnson's relationship, the last one three months before Katelynn came to stay with them.

It also includes five reports on domestic incidents from Irving's previous relationship and 84 reports regarding Johnson alone. Police would not necessarily have filed charges in those incidents.

"The existence of these documents, the information they contained, who was aware of that information, to whom the information was communicated, and what actions were taken as a result of that awareness and communication are all relevant to the assessment of the risks presented by Irving and Johnson, the genesis of the violence experienced by Katelynn, and a meaningful analysis of how that violence could have been prevented," the document read.

Police are expected to turn over the reports to the inquest Friday, but it's unclear if or when the motion will be heard.

Katelynn's mother, Bernice Sampson, was addicted to crack and gave her daughter to Johnson and Irving in a misguided attempt to give Katelynn a better life. Sampson's other children had already become wards of the Crown and she did not want to lose access to Katelynn in the same way.

It was later revealed that a judge granted custody to Irving despite her criminal convictions for prostitution, drugs and violence. Johnson also had a several convictions.

Katelynn was beaten for months until she died from complications from her injuries. Her battered body was found in the pair's apartment in the early hours of Aug. 3, 2008.

The couple pleaded guilty three years ago of second-degree murder in the girl's death and were sentenced to life in prison with no chance of parole for 15 years.

The inquest, which began Monday, has heard that two child welfare organizations -- the Children's Aid Society of Toronto and Native Child and Family Services -- were contacted about Katelynn or had dealings with the pair while she was living with them.

Had they been aware of the police reports, those agencies might have taken a more aggressive approach, the motion argues.

"Receiving information about any and all police attendances at the home is essential to agencies if they are to effectively assess risk to children and plan services accordingly," the document said.

Though the inquest focuses on the period between May 2007 and August 2008, "conflict and violence concerns go to assessment of risk and harm to children, and thus are not limited to the scope period," it said.

"The question is whether knowledge of the conflict and domestic violence would have influenced child welfare workers and service delivery. ... This is a critical issue in the Sampson inquest and may well lead to recommendations."

The inquest is expected to last four weeks and hear from 30 witnesses.