A sitting Alberta provincial court judge is rejecting allegations that the province's Justice Ministry buried key evidence in criminal cases that involved possible wrongful convictions.

In an unusual step for an active judge, Gregory Lepp is weighing in on a growing public controversy over disputed autopsies in Alberta, stating that a lawyer was well aware that a medical examiner's opinions had been rendered "useless" in a past review of criminal cases.

Lepp, formerly the head of Alberta's prosecution service, wrote a series of letters to The Fifth Estate in January and February disagreeing with a high-profile defence attorney who had accused the provincial Justice Ministry of burying evidence that might have exonerated his former client.

Lepp denies that he or his former staff did not fulfil their "disclosure obligations" to those charged with crimes and their lawyers.

Dispute concerns autopsies from 2010, 2011

At issue are some autopsies conducted in 2010 and 2011 by Dr. Evan Matshes, a forensic pathologist whose findings were instrumental in second-degree murder charges laid against three people in Western Canada.

The Fifth Estate reported last month that the Alberta Justice Ministry obtained expert opinions seven years ago that questioned some of the medical findings that supported those murder charges. Two defence lawyers and their clients said they were not given what could have been crucial evidence, despite a requirement that prosecutors share it with them.

Adriano Iovinelli defended Butch Chiniquay in court in 2012. He said he was not aware of an expert review panel's findings that called into question key facts in the case. (Dave Rae/CBC)

In a letter to The Fifth Estate from his legal counsel, Lepp said defence lawyer Adriano Iovinelli — who represented one of those charged — was clearly aware from media releases and news coverage that Matshes was "unreliable" in criminal cases reviewed by an external committee.

Lepp wrote that Iovinelli was aware that Alberta Justice ordered an expert panel review that "showed that Dr. Matshes was unreliable in any criminal case" under review and that his opinions back then were "useless to the prosecution."

Edmonton trial lawyer Tom Engel said that if Matshes's work was rendered "useless" in the five criminal cases studied by the panel, that finding alone raises concerns about all of Matshes's work.

Engel is a member of the Criminal Trial Lawyers' Association and one of its committee chairs, but he does not speak for the group.

Lawyers' Association calls for public inquiry

After completing more than 250 autopsies in Alberta, Matshes left the province in 2012 to work in the United States. He now lives in San Diego and provides expert testimony in criminal and civil cases across the country.

Butch Chiniquay, 34, was in prison when the autopsy in his case was reviewed. (Dave Rae/CBC)

The Criminal Trial Lawyers' Association has joined calls for a public inquiry into the autopsy scandal.

"It's obvious that they need to conduct a review of all these prosecutions," Engel said. "It will be a very large task."

Engel said it's important that the official running such an investigation be allowed to subpoena and cross-examine witnesses under oath.

As a result of The Fifth Estate investigation, British Columbia and Alberta have hired external counsel to review the conduct of their prosecution services, but those probes will be held behind closed doors.

Matshes continues to stand by his work and says he is the victim of a political vendetta. He disputes the findings of the expert review panel.

Lepp's letters to The Fifth Estate — sent through his lawyer — state that it is "absolutely false" that his prosecution service buried the findings of an independent external review report that found Matshes made unreasonable findings in 13 of 14 cases, including the five that resulted in criminal charges.

Lawyer, judge disagree on key point

Lepp was responding to comments made by the Calgary defence lawyer, Iovinelli, who told The Fifth Estate he never saw a key document — later obtained by journalists — that might have helped free his client from prison.

At the centre of the dispute between Lepp and Iovinelli is why his former client, Butch Chiniquay, sat in jail for several years without being aware of new information that might have exonerated him.

The peer review form related to the Chiniquay case says: 'The conclusion of homicide is not adequately supported.' (CBC)

The case goes back to 2011, when Chiniquay was charged with second-degree murder in the death of his girlfriend, Charmaine Wesley, a woman from Stoney Nakoda First Nation.

Chiniquay told The Fifth Estate that to avoid risking a possible life sentence, he took a plea deal in 2012 for manslaughter. He insists he did not kill his girlfriend.

"I just want to tell everybody, like, I'm innocent," Chiniquay said. "Nobody's gonna understand me, what I've been through. This is painful."

What Chiniquay didn't know at the time was that while he was serving his prison term of five years, Alberta Justice obtained a review of Wesley's autopsy. That review stated: "The conclusion of homicide is not adequately supported" and raised an earlier car accident as a potential cause of her fatal injuries.

Tom Engel is a board member of the Criminal Trial Lawyers' Association. (CBC)

"Why am I seeing this for the first time?" Iovinelli said when The Fifth Estate showed him the document. "You're not going to get [Chiniquay's] period of incarceration back."

Defence was aware of review, says former head of prosecution service

In January, Lepp sent The Fifth Estate a letter that pointed the finger back at Iovinelli. He referred to the Alberta Justice public media release and related newspaper coverage about the expert review. That media release said that Dr. Matshes made unreasonable findings in 13 of 14 cases reviewed but did not provide names or specific results.

Lepp wrote that Iovinelli had been quoted in a newspaper article at the time, agreeing that the negative review of some of Matshes's autopsies would benefit an accused and not the prosecution.

Lepp cited that newspaper clipping as a factor in stating the Alberta Crown Prosecution Service met its disclosure obligations in the Chiniquay case.

Lepp said it was obvious from Iovinelli's comments that "he was clearly aware, back in 2012, of the existence of the report and that the report essentially rendered whatever opinion Dr. Matshes provided in any criminal case [that was reviewed], including Mr. Chiniquay's, useless to the prosecution."

'It was made available'

Lepp later added, "with respect to your inquiry regarding Butch Chiniquay, it is clear from publicly available records that Mr. lovinelli was aware that the external review committee report showed that Dr. Matshes was unreliable in any criminal case [reviewed]."

Lepp also said that in 2012, he assigned a senior prosecutor to "ensure that appropriate disclosure" was made to all defence counsel. That prosecutor, Lepp said, told Iovinelli directly further disclosure was available.

"It was made available, and receipt of it was declined," Lepp said.

The Alberta Crown Prosecution Service (ACPS) "could only assume that Mr. lovinelli's declining of further disclosure regarding Dr. Matshes was based on informed instructions from his client, Mr. Chiniquay. The ACPS fully met its disclosure obligations in this case."

Lepp said Alberta Justice confirmed in a letter to lovinelli that he "did not require further disclosure relating to Dr. Matshes."

'How can they not act upon it'?

Iovinelli bristled at any suggestion that he was at fault for not looking at the document. He said that while he may have been aware of the review of Matshes's work, no one told him about a crucial document called a peer review form that, had he known about it, might have set his former client free.

"They had it," he said, referring to the Crown. "How can they not act upon it?"

Iovinelli said at no time did Lepp's Crown prosecution service ever tell him of the potentially significant content of that document.

"Well, no one told me what that disclosure was, to start off with," Iovinelli said.

He said he does not remember turning down an offer to see a document.

Lepp responded that there was no obligation on the part of the prosecution service to say precisely what was in that document.

"The Crown is never required to summarize or highlight portions of relevant disclosure," he wrote.

'They can't just let that ride'

Engel said Alberta Justice had an obligation to act on that information whether or not Chiniquay's former lawyer passed up an opportunity to see it.

"If they [Alberta Justice] think that there could be a miscarriage of justice, and they have a lawyer who they claim is just not doing anything, they can't just let that ride," he said.

"They have to do something .... They could initiate an appeal to the Court of Appeal.... But sitting back and relying on defence counsel doing nothing, that's not acceptable."

Tammy Bouvette, 36, says she never received a crucial piece of evidence that could have helped her defence in her criminal case. (Doug Husby/CBC)

Iovinelli also noted that he was not Chiniquay's lawyer at the time that Alberta Justice obtained the peer review form that stated there was not adequate evidence of homicide.

Legal experts consulted by CBC said if Chiniquay did not have a lawyer acting for him, then prosecutors had an obligation to reach out to Chiniquay directly.

Lepp did not respond to questions from The Fifth Estate on this point, stating he would not be providing further comment given the recent announcement of a planned review by outside counsel.

Legal experts consulted by The Fifth Estate also said that while it was "unusual" for a provincial court judge to engage in this kind of discussion about criminal cases, it is not improper and can be seen as helping the public understand what happened.

They pointed out that Lepp was describing events that occurred when he was a prosecutor and not a member of the judiciary.

At the same time, those experts say judges have to consider the weight of their words in the context of the office they now hold — and ensure that they not appear to take sides on issues they might also be adjudicating in their courtrooms.

Convictions may 'need to be expunged,' lawyer says

Asad Kiyani, a law professor at the University of Calgary, said defence counsel should ask prosecutors for any additional disclosure as it arises but said the Crown is required on its own to also provide any information to the defence that is relevant to the case.

"The obligation is not just to disclose, but to ensure that people who are wrongfully convicted are not in jail," Kiyani said. "And if they have spent time in jail, then we need to think about whether those convictions need to be expunged."

The Fifth Estate identified another second-degree murder case where a defence lawyer and former client say the Crown prosecutor in the case did not provide them the key peer review form that disputed some of Matshes's opinions.

Tammy Bouvette took a plea deal in 2013 for criminal negligence causing death in the drowning of a toddler she was babysitting in Cranbrook, B.C.

She said she took the deal to avoid the risk of a longer sentence and insists what happened was a tragic accident. Today, she is homeless outside Vancouver and says she still lives with the stigma of being accused of deliberately killing a child after what Matshes told prosecutors.

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

Alberta Justice says it did, in fact, provide the B.C. Crown's office with the peer review form that disputed comments made by Matshes after his autopsy.

Bouvette's lawyer, Jesse Gelber, said he specifically asked for additional disclosure from the B.C. Crown but says he was never given that information, nor was he told about the existence of the peer review form affecting his case.

Disputes over disclosure also occurred in other cases

The Fifth Estate also identified two additional criminal cases in Alberta that were reviewed by the expert panel, and where some of those involved say they did not receive those findings.

Lepp wrote that in the case of Shelby Herchak, charged with second-degree murder in the 2010 death of her son, the Crown provided full disclosure to her defence lawyer.

When contacted recently, Herchak told The Fifth Estate she never saw a document that disputed parts of Matshes's autopsy findings and might have changed the outcome of her case. She told The Fifth Estate she accidentally dropped her baby but took a plea deal of manslaughter to avoid a possible life sentence.

Herchak's lawyer, Kim Ross, did not respond to repeated emails attempting to verify Lepp's comments.

Dr. Evan Matshes studied at the University of Calgary. (University of Calgary)

Matshes took Alberta Justice to court in 2013 over how the government conducted the expert review panel that produced the key documents disputing some of his forensic pathology findings. The ministry agreed to "quash" the expert review panel results, as Matshes had successfully argued he had not been given enough time to respond.

At that time, Alberta Justice stated that "the administration of justice" demanded a second panel be convened to again review the 14 Matshes cases. Neither Lepp nor Eric Tolppanen, the current head of the Alberta Crown Prosecution Service, responded to queries about why the second review never happened.

Tolppanen said the quashing rendered the panel's findings "inconsequential."

Matshes also sued the Alberta government for defamation in 2014 after the review of his autopsies was announced. His $30-million lawsuit has not been settled.

Judge welcomes external review

Lepp said he welcomes the newly announced external probe into the prosecution service and is "anxious to provide full co-operation."

"It is important that the truth be revealed publicly," he said.

In recent years, Chiniquay served out his sentence and moved back to his family home.

"I've been honest since Day 1. I was looking for this right from the beginning and didn't know where to start," Chiniquay said about the new findings.

"Maybe one of these days, things change, possibly longer. Miracles happen."

Chiniquay is living back home with his family and pets. (Dave Rae/CBC)

Iovinelli said he wants the dispute with Lepp and Alberta Justice to be over and to see his former client get justice.

"I've been practising 25 years, I hope to practise many more years, and I'm not going to get in a war of words with the judge," Iovinelli said.

The entire dispute comes down to one question, he said: "Why didn't the Crown's office act on this?"

"And all we're waiting for is an answer," he said.

WATCH | The full The Fifth Estate documentary series, The Autopsy:

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

In part two The Fifth Estate tells the inside story of how senior Alberta government officials ultimately abandoned their probe into miscarriages of justice. 28:30

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