Ontario's chief pathologist has cast doubt on the exact time when a 12-year-old murder victim died, as a review of the 1959 murder conviction of Steven Truscott, Canada's youngest-ever death-row inmate, got underway Monday.

An original autopsy concluded that Lynne Harper died in the early evening. But Doctor Michael Pollanen said there wasn't enough evidence to draw that conclusion. He said she could have died the following day.

Steven Truscott, pictured in 2004, has always maintained his innocence and is hoping to be fully exonerated.
(Adrian Wyld/Canadian Press)

The lack of decomposition in the days following her death made it difficult to determine when she died, he testified.

Harper's remains were exhumed in April. Pollanen said her remains were "skeletonized" and of little forensic use. Investigators were unable to extract any DNA evidence that would have shed more light on the case.

Truscott served nine years in prison for Harper's sexual assault and murder. He has always said he is innocent. Truscott is hoping this review of his case will clear his name.

Author Julian Sher says the appeal will be Truscott's 'last, best chance' to clear his name.
(CBC)

Fresh testimony will be heard by the court in the case, including from witnesses who were young children at the time of Harper's murder.

Truscott was 14 when he was accused of raping and strangling Harper, a classmate in the town of Clinton, Ont., about 100 kilometres north of London.

Within three months of Harper's killing, Truscott had been sentenced to hang for the crime. His sentence was later commuted to life in prison, and his conviction upheld by the Supreme Court in 1966.

Truscott was released on parole in 1969 and has always maintained his innocence. He is hoping to be fully exonerated.

"Finally, this will be his last, best chance to [clear his name]," Julian Sher told CBC News.

Sher is the author Until You Are Dead, a book about the Truscott case. Last week, the court ordered him, fellow journalist Theresa Burke and the CBC to turn over videotapes of two people interviewed for an episode of CBC Television's The Fifth Estate that dealt with the case. 

In 2002, the federal government ordered a judicial review of Truscott's case. It concluded that a miscarriage of justice had likely occurred, although it drew no conclusions about his guilt or innocence.

Based on the review, then justice minister Irwin Cotler referred the case to the Ontario Court of Appeal.

In addition to residents of Clinton, witnesses to appear in front of the five-judge panel are expected to include experts on pathology and entomology. One of the key issues could be the time frame of Harper's murder, which has long been a contentious issue.

Sher told CBC News there is a dichotomy at the heart of the case that has kept it compelling after so many years.

"Steven Truscott, in the eyes of many, has been seen as acquitted, but he's not," Sher said.

"He's a convicted murderer on parole still, but he has been acquitted in the court of public opinion — so many people believe his story."

Crown and defence lawyers will present written arguments after the testimony, which is expected to last three weeks, but won't make oral presentations until January.

The appeal court could set aside Truscott's conviction or allow it to stand. If it sets the conviction aside, it then has three options: acquit him, issue a stay of proceedings without an acquittal, or order a new trial.

A decision isn't expected until spring 2007.