The Ontario government is promising to hold a public inquiry into the work of former pathologist Dr. Charles Smith, Premier Dalton McGuinty announced Friday.

"Given that people may have been wrongfully convicted . . . and thereby wrongfully imprisoned, we have a heavy responsibility to ensure that we have the kind of process in place that gets to the bottom of this,'' McGuinty told reporters in Barrie, Ont., after visiting a local hospital.

"We are going to have an inquiry. It is going to be public, but (what) the parameters are, we're not exactly sure yet.''

The announcement comes a day after a review of Smith's work found that he had made errors in 20 child autopsies. Thirteen of those cases resulted in criminal convictions, and one person is still behind bars.

The inquiry will begin after former Ontario Superior Court chief justice Patrick LeSage completes an audit, announced on Thursday, on how forensic pathology reports are handled to prevent future problems. 

Earlier Friday, a woman wrongly charged in the death of her daughter made a public appeal for an independent inquiry.

Brenda Waudby, of Peterborough, Ont., told Canada AM on Friday that she was charged in 1997 for the death of her 21-month-old daughter, Jenna, based on Smith's faulty conclusions.

"I've been calling for an inquiry for five years. It's time. We should have had one done in all the cases a long time ago," she said.

"This can't happen anymore, the government has to take responsibility now."

In Waudby's case, Smith said the girl had died of blunt trauma inflicted when she was home alone with her mother. The murder charge against Waudby was eventually withdrawn after medical experts disagreed with Smith's findings.

After 10 years, one of Jenna's babysitters finally confessed to an undercover investigator.

Because of Smith's errors, Waudby was separated from her two other children and suffered intense emotional pain.

"I remained a suspect up until December of 2005, when the babysitter was arrested," Waudby said.

The review

On Thursday, Ontario Chief Coroner Dr. Barry McLellan told reporters that the five forensic pathologists who reviewed Smith's work expressed concerns in 20 cases he worked on, "with respect to the conclusions reached by Dr. Smith or with a significant fact arising from the work that he did," he told reporters.

McLellan apologized to the families of deceased children whose autopsies were involved in the review.

"Wherever possible, families were contacted directly prior to the start of the review, to inform them that the death of their child was included in the review," he said.

"I sincerely regret the fact that some families who had moved on or who were in the process of moving on with their lives, following the death of their child, may have been subjected to any additional stress as a result of the process."

The 13 cases that had resulted in convictions will now be reviewed by Crown and defence lawyers. Those reviews will be separate from the public inquiry announced Friday.

Ontario Attorney General Michael Bryant called the errors an "unspeakable tragedy."

"This is not supposed to happen," he said. "It should not have happened, it's unacceptable that it happened, it's wrong."

The independent review into 45 of the autopsies Smith performed began in June 2005, after several cases he had worked on collapsed.

In many cases, people -- including the parents of the children involved -- were convicted in their children's deaths.

Smith resigned as chief pediatric pathologist at Toronto's Hospital for Sick Children two years ago, and took an appointment with the Saskatoon Regional Health Authority.

He was later fired. But last year, an appeals tribunal ruled he was unfairly terminated.

Smith was involved in more than 1,000 autopsies for the Ontario Office of the Chief Coroner.

With reports from CTV's Paul Bliss and Chris Eby in Toronto