WINNIPEG - A Manitoba couple found guilty of murdering the woman's young daughter want new trials unless their convictions are reduced to manslaughter.

In separate briefs filed with the Manitoba Court of Appeal, Samantha Kematch and Karl McKay argue they were unfairly convicted of first-degree murder. They point out they denied during their trial that they confined five-year-old Phoenix Sinclair to a basement where she died on the cold floor after the last of many beatings.

Under the Criminal Code, someone is deemed to have committed first-degree murder instead of second-degree murder or manslaughter if he or she forcibly confined the victim at the time of the slaying.

The verdict was "contrary to law and against the weight of evidence" reads a factum filed by Kematch's lawyer, Leonard Tailleur.

Kematch and McKay were sentenced last December to life in prison for the neglect and repeated beatings that killed Phoenix. The girl's stepbrothers testified she was often hit, choked, shot with a BB gun and forced to spend days and nights lying naked in the basement of the family's home on the Fisher River reserve north of Winnipeg.

There was also testimony she was forced to eat her own vomit.

Experts told court the girl had suffered repeated injuries over a long period of time, and had broken bones all the way from her pelvis to her skull. She died after a beating in June 2005, but her death went unnoticed until March of the following year.

The Crown successfully argued the killing qualified as first-degree murder because Phoenix was forcibly kept in the basement. McKay's lawyer argues that while the girl was sometimes told to stay in the basement, and occasionally penned in behind a washer, she was not physically restrained at the time of her death.

"The trial judge misapplied the law in concluding that forcible confinement ... could be made out by psychological constraint alone," reads the factum prepared by lawyer Mike Cook.

"There was no evidence of any physical confinement ... that could be causally and temporally linked to Phoenix's death. The trial judge should have directed an acquittal on first-degree murder."

Kematch and McKay, who was her live-in boyfriend, pointed the finger at each other for Phoenix's death both in court and in jailhouse interviews. They also argued the trial judge was wrong not to grant them separate trials. Kematch's defence team wanted to present evidence that McKay had a history of being violent towards women, Tailleur says, but was limited by the trial judge because the couple was being tried together.

The death of Phoenix sparked a review of Manitoba's child welfare system, and will be the subject of a public inquiry once legal proceedings are finished.

The little girl was in foster care for much of her short life, but was returned to her mother in 2004. In early 2005, a child welfare worker went to check on the youngster. He never saw Phoenix, but noticed a sibling playing outside the family home and decided everything was fine.

Three months later, Phoenix was dead. Her body was wrapped in garbage bags and buried in a shallow grave near the Fisher River garbage dump. Her death went undetected until one of McKay's sons contacted police.

Their appeal is to be heard Oct.13.