UPDATE: This story has been updated to reflect new information provided after publication by Judge Greg Lepp, former head of Alberta's Crown Prosecution Service.

Butch Chiniquay was only months into a lengthy prison sentence in the death of his girlfriend, Charmaine Wesley, when senior officials in Alberta's Justice Ministry obtained a report that might have exonerated him.

An initial autopsy had found that Wesley's 2011 death was a homicide, and that her injuries were "inflicted trauma." Chiniquay was charged with second-degree murder.

But a later medical report written in November 2012 by a panel of expert pathologists concluded that there was no adequate evidence of homicide and that Wesley's injuries in a car accident were a possible cause of her death.

An investigation by CBC's The Fifth Estate has found that report, commissioned by Alberta Justice, was never provided to Chiniquay or his lawyer.

I am telling the truth, and I am innocent. - Butch Chiniquay

In a recent interview, The Fifth Estate host Mark Kelley showed Adriano Iovinelli, Chiniquay's lawyer, the previously undisclosed medical finding.

"Why am I seeing this for the first time?" Iovinelli said. "You're not going to get [his] period of incarceration back."

Chiniquay, 34, said he feels vindicated by the new revelations.

"I am being honest, and I am telling the truth, and I am innocent," he said during an interview at his home on Stoney Nakoda First Nation, 60 kilometres west of Calgary, where he now lives after being released from prison. "I did not kill her."

These revelations come as part of a six-month The Fifth Estate investigation that found senior officials at Alberta Justice were aware of a report that shook the foundations of several murder charges and cast into doubt numerous findings of a medical examiner in Calgary a decade ago.

Inquiry launched

At issue were some of the autopsies performed by Dr. Evan Matshes, a forensic pathologist working out of the Office of the Chief Medical Examiner in Calgary in 2010 and 2011. After concerns were raised about some of his findings, Alberta Justice launched an inquiry into whether or not there had been miscarriages of justice relating to autopsies.

Alberta Justice eventually decided to hire an external review panel of three U.S. forensic pathologists to assess Matshes's work.

The panel later stated their opinion that Matshes had made "unreasonable" findings in 13 of 14 cases reviewed. Five of those cases were related to criminal charges.

Yet The Fifth Estate has learned that in several criminal cases, those findings were not provided to defence lawyers or their clients, and that the report was buried for years by Alberta Justice — even as the incarcerated were serving their sentences.

Watch the full Fifth Estate documentary, The Autopsy Part 1: What If Justice Got It Wrong?

An autopsy tells the story of the dead but can also determine the future of the living. 30:22

Iovinelli said that it is up to Alberta Justice to explain why those reports were not released to defence lawyers.

"This is a significant difficulty that has to be addressed by the government, it just has to be," Iovinelli said.

Alberta Justice declined repeated requests to speak to The Fifth Estate.

Eric Tolppanen, the head of Alberta's Crown Prosecution Service, said in a statement that information was provided to defence lawyers "where required" and that they are "confident" that they met their "disclosure obligations."

Tolppanen did not elaborate about what, if any, disclosure was provided or to whom.

Legal experts consulted by The Fifth Estate say Alberta Justice was required by law to disclose any relevant documents to defence lawyers.

Lawyer Adriano Iovinelli represents Chiniquay, who went to prison for manslaughter. (Justin Pennell/CBC)

"It's not a question you have to give any thought to at all," said James Lockyer, a lawyer with Innocence Canada and an expert in wrongful convictions cases. "Alberta Justice has a lot to answer for."

Internal email correspondence shows that Alberta Justice acknowledged it must "disclose to the defence what we know."

Court records also show that Greg Lepp, then head of the Alberta Crown Prosecution Service, and now a provincial court judge, acknowledged Alberta Justice had a "constitutional" obligation to disclose the results of the expert review to defence lawyers.

'Critical to the outcome'

Alberta Justice also stated the findings of a medical examiner was often "critical to the outcome of court cases."

"The deputy (minister) is particularly concerned about whether there is someone in prison," Lepp said in a 2012 email to several senior justice officials.

Tolppanen said that Chiniquay's lawyer Iovinelli was aware that "additional disclosure regarding Dr. Matshes was available" and that Iovinelli told Alberta Justice he did "not require this further disclosure."

Dr. Evan Matshes performed more than 250 autopsies in his time at the Calgary medical examiner's office. Thirteen of those autopsies were reviewed by an external panel. (4patientsafety.org)

Iovinelli bristled at that suggestion. "At no time was I ever told that there was a peer review done that indicates that this is not a homicide," he said. "And more importantly, if they had that in their hand, why didn't they do something about it?"

Matshes declined to speak to The Fifth Estate.

"I stand by my work," he wrote in a statement. "I have devoted my professional life to making sure that the criminal justice system holds those guilty responsible for their crimes and does not prosecute the innocent."

Insurance company raised concerns

Alberta Justice began looking into Matshes's work in early 2012 after an insurance company raised concerns about one of his accidental death autopsies. Internal records show officials were most concerned about possible wrongful convictions.

A panel of three forensic pathologists was selected to review several of Matshes's autopsies, including cases that had already led to second-degree murder charges.

One case involved 18-year-old Shelby Herchak, who was described in news headlines as a "baby killer." In 2010, she was charged with second-degree murder after her 26-day-old son Daniel died of blunt-force trauma to the head. Herchak later accepted a plea deal for manslaughter and served more than five years in federal prison.

Shelby Herchak's son Daniel died in 2010. She was sentenced to 5½ years in his death. (Harvey Cashore/CBC)

The original report by Matshes stated there were multiple injuries to Daniel's head, including one that was seven to 15 days old.

To the police, that meant intent. Herchak was charged with second-degree murder.

"That medical examiner deemed me a monster," Herchak said in a recent interview at her home in Calgary's south end.

No one told Herchak that senior officials in Alberta Justice — including some who are now judges — had initiated that review of Matshes's work. Her son's autopsy was among the cases reviewed.

That report could have been critical to Herchak's defence because it questioned two key facts the Crown asserted to the judge ahead of her sentencing.

'It was an accident'

The expert review panel disputed that there was evidence of that earlier injury to Herchak's infant son, Daniel. They also raised concerns that Matshes may have mistaken a natural separation in a newborn's skull, which is not fully fused, with a fracture.

The possibility there was a single injury to Daniel's head would have fit Herchak's assertion that she dropped her baby after waking up suddenly.

"I did not kill my son. It was an accident. I dropped him," Herchak said.

James Lockyer is a lawyer with Innocence Canada. (Doug Husby/CBC)

Alberta Justice was provided the new evidence contradicting Matshes's report long before her murder trial was to begin.

Greg Lepp, a provincial court judge and the former head of Alberta's prosecution service, says his department disclosed that evidence to Herchak's then-lawyer, Kim Ross. Ross has not responded to queries to confirm Lepp's statement. Herchak said she was not told of its existence.

Lockyer said Alberta Justice was obligated to provide it.

"You have three pathologists who have reviewed the case and reviewed the original autopsy and all three of them are agreed that the original autopsy report was erroneous, wrong," Lockyer said.

'I couldn't do it anymore'

Without that evidence, Herchak told The Fifth Estate she agreed to plead guilty to manslaughter in order to avoid a life sentence for second-degree murder.

"To go through trial on a second-degree murder charge knowing that the medical examiner, all the stuff that he said, the judge and the jury would have believed him over anything that I said," Herchak said.

"I just gave up, I couldn't do it anymore, I didn't want to go to jail for life."

In January 2012, Chiniquay also agreed to plead guilty to manslaughter to avoid going to trial on his second-degree murder charge. He was sentenced to five years in prison.

Who dropped the ball? - Adriano Iovinelli

Lockyer said the accused's decision to agree to a manslaughter plea bargain is not unusual in the circumstances.

"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," he said.

The Fifth Estate showed Herchak a copy of the expert review panel report for the first time — seven years after it was written.

"Who in their name would bury a piece of paper so far down to make sure that nobody saw it, and send someone to jail for 5½ years? And with the name 'baby killer' for the rest of her life," Herchak said.

In his statement, Matshes told The Fifth Estate he has been the victim of "personal vendettas" and "local politics."

Not properly consulted

In a series of letters and emails to Alberta Justice in 2012 and 2013, Matshes and his lawyers asked that the findings of the review panel be set aside. Initially, Alberta Justice vigorously defended its process and the findings of the report. Officials with the ministry said they were concerned about possible miscarriages of justice and the impact on murder cases.

Then in November 2013, Alberta Justice conceded in court that Matshes was not properly consulted. Both parties agreed to set aside the expert panel report. A judge formally approved the agreement and issued an "order to quash."

At the same time, Alberta Justice told the court that it was "integral" that they continue their probe of Matshes's work.

"The minister also asserts that the administration of justice demands a new external review panel be conducted," said Marta Burns, then senior legal counsel and now a superior court judge with Alberta's Court of Queen's Bench.

Alberta Justice did not respond to The Fifth Estate's queries about why that second review has not taken place, six years later.

Herchak says she first saw the second autopsy opinion when shown it by The Fifth Estate. (Doug Husby/CBC)

"Nothing has happened," said Butch Chiniquay's lawyer Adriano Iovinelli. "Who dropped the ball?"

In an email, head Crown prosecutor Eric Tolppanen said that because of the decision to "quash" the report, the findings are therefore "inconsequential."

Matshes is now suing Alberta Justice, his former boss in the medical examiner's office and the expert panel members for $30 million for defamation.

The Fifth Estate obtained the expert review reports and other related documents from two court actions initiated by Matshes against Alberta Justice.

'Significant problem'

The Fifth Estate asked forensic pathologist Dr. John Butt for his opinion of review panel findings and related court documents.

"What this suggests to me is that there is a significant problem with the work that was done by Dr. Matshes," said Butt, who has helped develop medical examiner legislation across Canada. "My understanding now is that the justice department swept this whole thing under the rug."

Some of the most senior members of Alberta Justice, including the then-ministers, were involved with and co-ordinated the review of potential miscarriages of justice relating to those autopsies.

The review of Matshes's work was directly under the purview of Lepp, now a provincial court judge, then head of the Alberta Crown Prosecution Service.

"We have a constitutional obligation to disclose anything that affects the case[s] to defence counsel," Lepp said in sworn court testimony in 2013. "And we also have an obligation as prosecution service to consider this situation and determine what steps, if any, we're going to take in relation to these cases."

Eric Tolppanen is the head of the Alberta Crown Prosecution Service. (Alberta Courts)

Reached at his office in Edmonton's provincial court, Lepp said he could not discuss whether disclosure had been provided.

"You're just going to have to pursue those enquiries elsewhere since it's just not advisable, it's not a good course of action for a judge to comment on what happened prior to his appointment," Lepp said.

He added, "the [justice] department's responsible for the decisions that were taken years ago."

Why would you just shuffle the paperwork deep down and, like, destroy someone's life? ​​​ - Shelby Herchak

Marta Burns, the former senior counsel for Alberta Justice and now a judge, declined to respond to questions in a statement sent by her spokesperson.

"In her capacity as litigation counsel with the legal services division, Justice Burns was not charged with making disclosure to defence counsel," the statement said. "Decisions in this regard are made by the Crown Prosecution Service."

Tolppanen, the current head of Alberta's Crown Prosecution Service, did not respond to questions about why the second review panel was never convened — after his ministry said justice required it happen.

Current Alberta Justice Minister Doug Schweitzer declined The Fifth Estate's request for an interview. (Rachel Ward/CBC)

Doug Schweitzer, the current Alberta justice minister, also declined a recent request for an interview with The Fifth Estate.

"This matter predates the minister's time in office," his spokesperson said in an email.

Living with the consequences

While the charge goes back almost a decade, Herchak said she is still living with the consequences of a miscarriage of justice.

"Why would you just shuffle the paperwork deep down and, like, destroy someone's life?" Herchak said. "That's my life, right there, that could have changed. But instead, I have this to deal with."

Send tips on this story to Harvey.Cashore@cbc.ca or Rachel.Ward@cbc.ca or call 416-526-4704.

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