Colin Marr, 23, died from a single blow from a kitchen knife in July 2007 following a row in his Lochgelly flat with his fiancee, Candice Bonar, about his alleged infidelity.
His family challenged a police verdict of suicide after a number of red flags emerged in the wake of his death. A key concern is that several pathologists told a Fatal Accident Inquiry (FAI) in 2011 that it would have taken “considerable force” for Colin to have stabbed himself through the bone of his own sternum, where the kitchen knife was recorded to have passed through in the original post-mortem report.
But a 2012 Strathclyde Poilce cold case review, which commissioned the Centre of Anatomy and Human Identification at Dundee University, concluded the knife had most likely entered the chest plate to the right of the border of the body of the sternum, making suicide more plausible if the blade passed through soft tissue rather than bone.
The BBC now reports that material handed to the Crown Office by Colin’s family includes findings of a report by leading pathologist Dr Nat Carey, who says it was “both possible and plausible” that Colin’s injury was “inflicted by a third party” and questioned previous police reports on the location of the stab wound.
Dr Carey is known for his work on the Hillsborough disaster and Soham murders.
Ms Bonar - who now lives in Australia - has always maintained her innocence. Colin’s mum and stepdad, Margaret and Stuart Graham, have never accused her of being responsible but insist questions remain unanswered.
Mr Graham told BBC Scotland the family “welcomes any further inquiries into the significant evidence shared.”
He said a priority for the family is that prosecutors “quickly establish the actual wound location as outlined by Dr Carey, and the significant implications to the previous findings from fingerprint experts.”
Mr Graham also said there were “other significant statements” they have shared with police about who went to the house and when, but said no one has asked for the contact information.
Both Fife police and the Crown Office previously produced reports that were critical of the original investigation and issued apologies to Colin’s family. The Police Investigations and Review Commissioner also upheld 12 complaints over the force’s handling of the case.
Ms Bonar has been interviewed three times by police and voluntarily appeared in person at the 2011 FAI into his death.
At the inquiry, sheriff Alastair Dunlop said he could not decide if the death was suicide or homicide.
Speaking after the FAI, Ms Bonar said: "My name is cleared. I have always been honest and declared my innocence throughout this heart-breaking nightmare.
"What Colin did, he did to himself and that's the truth."
A spokesperson for the Crown Office & Procurator Fiscal Service said: “Prosecutors are pursuing lines of inquiry identified in material received from Colin Marr's family.
"The Lord Advocate has instructed that once these inquiries are complete, all the available evidence should be reviewed by independent Crown Counsel with no previous involvement in the case.
"We appreciate the impact Colin's death and subsequent events have had on his family and hope they will be reassured by the new steps being taken."
Crown Counsel are senior lawyers who act with impartiality and the full authority of the Lord Advocate.
Colin, a Dunfermline Athletic supporter, had been waiting for his mum to come to his home in Lochgelly for dinner before the tragedy unfolded on July 10, 2007. The pair had spoken on the phone just 15 minutes before he was discovered lying on the floor.
The FAI heard that Ms Bonar had told a friend she was going to see Colin that evening to sort things out. She arrived at the flat some time between 7.22pm and 8.02pm. The phone call from Colin to his mum to check she was still coming for dinner was timed at 7.53pm. He did not mention on the call that Ms Bonar was there.
At 8.02pm, Ms Bonar phoned a friend who said she had been told by another friend that news of Colin’s affair was true. The couple were engaged at the time.
Ms Bonar told the FAI that she then had a row with Colin which resulted in her throwing her engagement ring to the floor and telling him the relationship was finished.
She said Colin gripped her arms and tried to stop her leaving - and she hit him with her handbag.
As she looked for her trainers, Ms Bonar said she heard banging from the kitchen and, in a statement to police, said Colin shouted: “I’ll kill myself if you leave me, I’ve got nothing to live for.”
She said she then came back to the living room where Colin told her he had stabbed himself and was clasping his hands over his abdomen before he collapsed. A knife from the kitchen was on the carpet close to where he died.
Detectives in charge of the investigation decided the death was most likely suicide and no forensic, fingerprint or pathology experts attended the scene on the night.
In a review of the handling of the case for the Crown Office, retired detective superintendent David Swindle ruled the death was suspicious and said it was “frustrating to understand why such basic and serious failings took place.”
This report led to the report in 2012 by the cold case review team at Strathclyde Police.
Concerns over dumbbell
In statements to police, Ms Bonar said she hit Colin with her handbag during their row. The original post-mortem examination identified “recent trivial abrasions” to his forehead with “no underlying bruising or deeper injury.”
But Dr Carey’s points out that police photographs in the aftermath at Colin’s flat show a dumbbell with a thread bar, and that there is a “real possibility” the abrasion on Colin’s forehead could have been caused by this object.
The pathologist said if Colin had been struck by the dumbbell and was unconscious or semi-conscious on the floor, it would be easy to imagine the subsequent infliction of a penetrating stab wound of the kind presented in this case.
Dr Carey said if an impact injury like this was closely followed by a stabbing and loss of circulation, then very little bruising would be expected and that it would be wrong to dismiss this injury as trivial.
The dumbbell was not forensically examined or retained as a police production after Colin’s death.
Detective Chief Superintendent Laura Thomson, who oversees homicide and governance review of Police Scotland, told the BBC previously: "Our sympathies remain with Colin's family and we acknowledge the severe impact his death and the subsequent inquiries have had on them.
"Strathclyde Police undertook an independent investigation and learning opportunities were identified from the initial investigation, which were accepted by Fife Constabulary.
"Any new information which may be received about Colin's death will be assessed and acted upon, as appropriate."