Did a killer walk free after this man's autopsy?

A battered body, neck abrasions and signs of a violent struggle.

When the RCMP first investigated the death of Preston Lochead at his home in Airdrie, Alta., in 2010, they called in the major crimes unit.

The body of Lochead, 36, was found in the basement of his home, next to an overturned table. His roommate told police he saw a man scurrying from the house after the discovery of the body.

Police suspected foul play, began interviewing witnesses and brought that man in for questioning.

But then came the autopsy.

Calgary medical examiner Dr. Evan Matshes told the RCMP that contrary to what they might have thought, Lochead died from cardiac disease.

And with no homicide, there was no crime to investigate.

The RCMP broke the news to Lochead's widow, Sally Wheeler.

"I was like, 'You've got to be kidding.' I was so shocked that this is what [the RCMP] was telling me," she said in a recent interview with The Fifth Estate's Mark Kelley.

Lochead's death is one of several cases that came under scrutiny in 2012. Alberta's Justice Ministry ordered a review of some of the autopsies done by a Calgary medical examiner after questions were raised about the accuracy of his findings.

Documents obtained by The Fifth Estate reveal that Alberta Justice commissioned that review, which exposed several potential miscarriages of justice.

Wheeler said the RCMP told her a few months after her husband died that the autopsy prevented them from laying charges.

"They mentioned that he had a blow to the head and a broken bone in his neck," she said. "But they couldn't take it any further because it hadn't been ruled a homicide and I was like, 'What?'"

Turns out Wheeler wasn't the only one to question the autopsy results.

Documents obtained recently by The Fifth Estate show that a second medical opinion from three expert forensic pathologists — written two years after Lochead died — differed from the original medical examiner's finding.

They wrote that Lochead's death was more likely a homicide by "strangulation."

Senior officials in the Alberta Justice Ministry received that report as part of a larger review of Matshes's autopsies, but the findings were buried in court files for several years until unearthed by The Fifth Estate.

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

Wheeler and roommate Jimmy Dean, who were both in the house the night of the death, say it was obvious to them from the beginning that Lochead was killed.

The evening started with Lochead acting as a Good Samaritan. He had gone out to pick up refreshments for an evening poker game and came back with two strangers he met at the store. The strangers claimed their vehicle had broken down at the side of the road.

Staying behind

Lochead, a friendly Maritimer and father of three whom Wheeler described as her "angel," wanted to make sure the stranded travellers would not freeze in the frigid November night.

Wheeler remembers the two men as Americans who spoke Russian. One of the men appears to have stayed late.

Dean went to bed early and woke up just before 7 a.m. to discover the body. He said when he was on the phone to 911, he heard movement in another room.

"That's when I seen this fellow standing in the hallway," Dean told The Fifth Estate. "I told him to stay and he opened the door and took off."

Dean and Wheeler said police later told them that the stranger from the hallway was hiding in an unlocked car down the road. The American was taken in for questioning and treated for injuries he claimed were sustained in a fight with Lochead.

Dean said the RCMP told him some of what the American said in the police interrogation.   According to the suspect, a struggle began after Lochead began to have concerns about who the visitor really was.

"That's how the fight started because the guy didn't want to give Preston his ID," Dean said.

Allowed to go back to U.S.

Soon after the death, local news reports indicated that the RCMP were already getting signals from the medical examiner that it might not be ruled a homicide.

"Police are still awaiting Monday's autopsy results to determine if the struggle contributed to Lochead's death or if he died from natural causes afterward," the Calgary Herald reported.

According to Wheeler, the RCMP told her the American was eventually allowed to return to the United States.

Wheeler said the RCMP told her: "We're keeping an eye on him and we're in touch with the police down there."

But months later, Wheeler said, the RCMP told her that the finalized autopsy report meant they could not lay charges.

A later review of 14 of Matshes's medical files would include Lochead's autopsy. That review, commissioned by Alberta's Justice Ministry, stated that the medical examiner made unreasonable conclusions in 13 cases. 

Why wasn't that guy brought back to Canada to face charges?- Sally Wheeler

Airdrie RCMP told The Fifth Estate recently that Alberta Justice did not provide them with the 2012 report pointing to the death as a homicide.

A major crimes investigator at the RCMP was assigned to check their old case file and did not find the report.

"There is no communication from Alberta Justice on this investigation," Airdrie RCMP spokesperson Cpl. Laurel Scott said in a recent email.

'Not aware of a formal review'

In their peer review report to Alberta Justice, the expert medical pathologists wrote that more "weight" should have been given to "strangulation" as the cause of Lochead's death.

"A homicide manner [of death] is more appropriate," the three pathologists wrote in their November 2012 critique of Matshes's original autopsy.

Wheeler is still confused about why nothing happened next.

"There was a fight, he's dead. It was so clear to me," Wheeler said. "Why didn't they reopen the case?"

Eric Tolppanen, now head of Alberta Crown Prosecution Service and then a senior justice official, declined an interview with The Fifth Estate. In a statement, he did not answer directly whether the expert review panel document was provided to the RCMP in Airdrie.

Tolppanen said that the RCMP were told that "this police file would benefit from additional peer review."

He said that the RCMP acted on that advice and later "sent the file to the Crown for review for possible charges."

Tolppanen said that Crown prosecutors determined there was "no reasonable likelihood of conviction."

'No communication'

However, the RCMP appear to dispute that version of events. 

The RCMP agree that in 2015 they discussed the case with the Crown prosecutor who did not support laying charges. However, the Mounties say they were not told about the expert peer review panel finding of a possible homicide.

"The RCMP is not aware of a formal review that was done on the [medical examiner's] autopsy report," Scott said in her email to The Fifth Estate.

Wheeler points the finger directly at Alberta Justice for not acting more quickly back in 2012 when they learned the death may have been a homicide.

"Why did nothing happen?" she said. "Why did it just stop there? So they determine he was killed, but then say 'Oh, I guess that doesn't matter?' That's not right."

Wheeler is calling on Alberta Justice to provide the documents to the RCMP so that they can reopen their investigation.

"Why wasn't that guy brought back to Canada to face charges?" she said.

Matshes declined repeated requests for an interview with The Fifth Estate. In statements to the CBC, he said he stands by his work.

In 2013, Alberta Justice agreed to set aside the report of the expert panel at his request. Matshes successfully argued he was not adequately consulted in the process and that the review was based on limited information. A judge signed off on that agreement in November 2013.

'Met the standard of care'

In a brief to the Court of Queen's Bench in Alberta, the justice minister said it was "integral to the administration of justice" that they continue to investigate the accuracy of Matshes's work and promised to hold a second review panel.

In a recent statement, Matshes said he was also cleared by an expert pathologist working for the Alberta College of Physicians and Surgeons in a related investigation.

"That expert reviewer, who was in possession of all of the evidence that I had at the time I certified the deaths, concluded that I met the standard of care in each case," he wrote.

I want somebody to apologize.- Sally Wheeler

The Fifth Estate has also obtained records from that college review. A complaint was made to the college in 2012 about the appropriateness of Matshes's dissections during some autopsies. The college ruled that Matshes was permitted to make those dissections.

The college forensic pathologist also concluded that homicide was a likely scenario in Lochead's death.

The college expert, whose name was redacted in the report acquired by The Fifth Estate, stated that although cardiac disease may have been a factor in the death, the ruling should have been "homicide," as the violent struggle precipitated any existing physical condition.

"If one determines that the cause of death was cardiac precipitated by the physical altercation, the manner becomes homicide," the college expert wrote.

'Blunt force injury'

The college's forensic pathologist also noted "evidence of blunt force injury" and "neck compression."

The college expert also contemplated the possibility of charges against the killer and noted that careful documentation of the injuries would be essential as the accused might try to argue self-defence.

"If charges were considered, a potential defence in this case would be self-defence. In such a case, documentation of all injuries to the deceased is essential," the college review wrote.

Today, Wheeler wants Alberta Justice held accountable.

"I want somebody to apologize to his family and to me and for all the people that cared about him," she said.

"They just looked at this information and decided it wasn't enough, it wasn't important enough. Well, Preston was damn important to us."

If you have tips on this story, email Harvey.Cashore@cbc.ca and Rachel.Ward@cbc.ca, or call 416-526-4704.

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