The office of B.C.'s attorney general has appointed one of the country's top defence lawyers to probe the conduct of prosecutors involved in a second-degree murder charge laid against a babysitter in 2011.

Marilyn Sandford, a Vancouver lawyer, was named as a special prosecutor Wednesday following inquiries by CBC's The Fifth Estate about why defence counsel was not provided a key report that contradicted evidence used to charge Tammy Bouvette of Cranbrook, B.C., with murder.

In May 2011, the then-28-year-old babysitter called 911 after she found 19-month-old Iyanna Teeple unresponsive in a bathtub.

Iyanna was flown to Calgary for treatment, where she eventually died.

Retired RCMP Cpl. Chris Faulkner told The Fifth Estate's Mark Kelley that the Mounties originally considered the death a tragic accident, after Bouvette said she left the baby to attend to a spill in another room.

"I don't believe that she ever intended to kill the child," Faulkner said. "And there's nothing in our investigation that would state that she intended to cause the death."

That all changed after a B.C. prosecutor heard from a Calgary medical examiner in October 2011.

Nineteen-month-old Iyanna Teeple was found face down in a bathtub on May 26, 2011. (Family photo)

Court documents obtained by The Fifth Estate show that the medical examiner who performed the autopsy, Dr. Evan Matshes, told prosecutors there was "no benign" explanation for some injuries found on the toddler and he identified bruising that was "typical of child abuse."

Three weeks after speaking with Matshes, B.C. prosecutors charged Bouvette. RCMP praised the "efforts of the medical examiner in Calgary" as being "instrumental in pushing the case forward."

The Fifth Estate discovered that medical experts were asked to review the autopsy after concerns were raised about some of Matshes' other findings. Alberta Justice had convened an expert panel to analyze his findings in 14 cases, including Iyanna's.

The panel of three forensic pathologists stated in their report that the comments Matshes made to the prosecutor about "intentional injuries" on the body and prior abuse were "unreasonable."

Bouvette's lawyer, Jesse Gelber, told The Fifth Estate he did not receive that review, despite asking the Crown prosecutor if further disclosure was available.

Tammy Bouvette is a victim of a miscarriage of justice. — James Lockyer, Innocence Canada lawyer

"I had no idea, that was not disclosed to me," said Gelber.

Jesse Gelber represents Bouvette, who in 2013 took a plea deal for criminal negligence causing death. (Doug Husby/CBC)

By law, prosecutors must provide defence counsel with all relevant documents in a criminal case.

Without knowing about the panel finding in her favour, Bouvette pleaded guilty to criminal negligence in order to avoid a life sentence for second-degree murder.

"I would say without qualification that Tammy Bouvette is a victim of a miscarriage of justice," said James Lockyer, a lawyer with Innocence Canada who has reviewed the case files obtained by The Fifth Estate.

"We know from wrongful conviction cases in Canada … that people pleaded guilty to crimes they didn't commit because they were facing a murder charge, and so to avoid the potential life sentence took a plea to a lesser crime for a shorter sentence."

For his part, Gelber said the damage will never go away for his client.

"There was a horrible stigma, and that stigma even extended to her family and her children," he said. "It was devastating for her."

'Shame on them'

The Fifth Estate found Bouvette, now 36, living homeless in New Westminster, just outside of Vancouver.

"I am not a baby-killer … People just look at me differently like I was some type of monster and I'm not," she said, before the special prosecutor was appointed. "I'm a loving person and a loving mom."

Bouvette said knowing about the panel's review of the autopsy has taken "a big weight off my chest, it makes a big difference."

Still, she will not forgive those who did not disclose that information when it would have really mattered.

"Shame on them for not doing their job right," Bouvette said. "It has taken everything from me: my freedom, my whole self, everything."

The Fifth Estate investigation has found that a defence lawyer in another second-degree murder case in Alberta says he did not receive an autopsy review.

Bouvette is featured in a Fifth Estate documentary. (Doug Husby/CBC)

'Integral' to justice

In a statement, Eric Tolppanen, head of the Alberta Crown Prosecution Service, said Alberta Justice provided the documentation in Bouvette's case to B.C. Crown prosecutors.

The Fifth Estate later inquired with the B.C. Prosecution Service about whether it had received those documents. After waiting for a response for several days, journalists received the notice that the special prosecutor would be investigating the service's conduct.

The statement said the investigations results will be released at an "appropriate time" and that neither the Prosecution Service nor the special prosecutor "will comment further."

Tolppanen also said he views the findings of the expert panel as "inconsequential" because the Alberta government agreed to quash the findings after Matshes went to court. An Alberta Queen's Bench justice ruled that the panel's review was not fair to Matshes and that he had not been given enough time to respond or provide additional materials.

Although Alberta Justice agreed to the quashing. its lawyer told the court it was "integral to the administration of justice" that a second panel investigate the accuracy of Matshes's work. That was more than six years ago. So far there has been no second panel.

Matshes continues to stand by his work.

Watch The Fifth Estate documentary, The Autopsy Part 2, on Sunday. (CBC)

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