Hitman Robert Graham is facing a lengthy jail sentence after a jury found him guilty of a brutal knife attack on Mr Cumming, whose job was to investigate crooked lawyers.
Now detectives have said there may be “further inquiry” into the motive behind the hit outside Mr Cumming’s Murrayfield home in January 2006.
The trial heard that Graham, who was living under a fake identity after arriving in Britain 12 years ago from New Zealand, confessed to a workmate that he was paid £10,000 by a man in a BMW to give a target “a good working over”.
Detective Chief Inspector Keith Hardie, who has worked on the inquiry for a number of years, said he continued to believe “someone set up Graham to carry out the attack”, but added officers would be “directed by Mr Cumming” over possible suspects.
In the days after the attack, Mr Cumming, 68, drew up a list of names of suspects after trawling his extensive files as chief accountant for the Law Society of Scotland to find individuals with a motive, and at least four individuals were interviewed.
One of those questioned was an Edinburgh lawyer who was also linked to pair of baseball bat attacks on the homes of Lothian businessmen in October 2005, just three months before Mr Cumming was left scarred for life.
Mr Cumming spearheaded a crackdown on all forms of misconduct relating to finance before he was targeted. He suffered several knife wounds in the assault at a lane at the rear of his home in Murrayfield Drive, on January 23, 2006.
But before two teams of surgeons began to operate on him, a doctor took swabs from around his fingernails as he lay anaesthetised ready for theatre, which would help provide crucial DNA evidence against Graham.
Graham, who was born in Ireland as Paul Francis McGhee before emigrating to New Zealand at the age of nine, finally came to police attention after being arrested in January 2009.
DCI Harvie said: “Mr Graham was arrested for drink-driving down in Hampshire and during that process a DNA swab was taken from him.
“The profile we had was regularly searched on the database and that’s how we got the match.”
Police raided his former partner’s home in Pilton Avenue, but DCI Harvie said that Graham had fled to Australia just days after his arrest, a discovery made after officers traced his passport number. He was extradited back to the UK and first appeared in court in February.
The former tanning salon boss and scaffolder stood trial at the High Court in Edinburgh after denying the attempted murder of his victim under the name of Robert Leiper Graham, which he has used since arriving in Britain in 1999 with an illegally obtained passport.
He left New Zealand in that year to escape drug-dealing charges.
Graham was found guilty by a majority verdict of the murder bid on Mr Cumming by repeatedly striking him on the head and body with a knife to his severe injury, permanent disfigurement and to the danger of his life.
Asked about Graham identifying himself as Paul Francis McGhee in court, DCI Harvie said: “I suspect that’s who he is. He is certainly not Robert Leiper Graham. I suspect he is Paul Francis McGhee.”
Graham, who is a martial arts exponent trained in rapid arnis, a Filipino martial art that uses knives and fighting sticks, had claimed in court that he had intervened in an attack on Mr Cumming by another man, known as “Gogs”, and had stopped him taking “a bigger hiding”.
Mr Cumming told the court that he parked his car at a garage in a lane at the rear of his home after returning from a training day with colleagues at a hotel.
He realised that a male figure in dark clothing and wearing a balaclava was coming towards him to confront him. He said: “Nothing was said. No demands were made, just silent, just walking towards me.”
Mr Cumming grasped the balaclava worn by his attacker as he made a bid to unmask his assailant, but he was repeatedly slashed in the face.
Forensic examiner Dr Rachel Miller, who saw him after the attack, noted more than 40 injuries with nearly 40 sutures put into face wounds after a “sustained, frenzied, vicious attack”.
The court heard that DNA analysis provided a “full” match from samples taken from the jacket and the victim’s hands with Graham.
After the verdict, Judge John Morris QC deferred sentence on Graham for a background report. He was remanded in custody and will appear for sentence on December 15.
Following the attack, the Law Society of Scotland contributed a £10,000 reward for information, and an appeal was later made on the Crimewatch TV programme.
Mr Cumming’s job was to oversee investigations into the accounts of solicitors who turn a blind eye to the laundering of money from drugs, prostitution and protection rackets.
Following the conviction, John Logue, area procurator fiscal for Lothian, said: “In 2006, Robert Graham targeted and tried to kill Leslie Cumming because he was paid to do so. Almost six years later, he has been found guilty of this vicious and cowardly attack after being extradited from Australia.
“I hope that (the) successful prosecution will secure the confidence of the Scottish public that those who try to evade justice will be pursued and brought before the courts.”
LESLIE Cumming has spoken about the “horrific and bloody” attack he suffered as he praised police for their work in catching Robert Graham, below.
Speaking at a press conference, Mr Cumming said: “It’s almost six years since I last sat in this room, making an appeal for information about the attack on me in January 2006.
“Since then, the family has obviously tried to live an ordinary life, but from time to time I got an update of progress on the investigation and so we knew the case had never been closed. In fact, the police perseverance and professionalism, and the Crown Office input, has been vital in securing the result today.
“It’s important to me that I got that closure and I just want to thank the members of the team who were involved in this complicated case for their efforts on my behalf.
“The actual event was horrific and bloody, and having to explain to the court in such detail as we could recall at this time was traumatic for my wife and me.
“I hope now the trial is complete and the result is known that this nightmare has ended for us and we can get back to normal life.”
FIVE YEARS ON ROAD TO JUSTICE
• January 23, 2006, 5.10pm: Leslie Cumming is stabbed outside his home by a masked attacker.
• January 31: Detectives say they are convinced the stabbing was the work of a hitman or someone else bent on revenge.
• March 21: Mr Cumming speaks publicly about his ordeal for the first time at a police press conference.
• January 8, 2007: Detectives say they are pinning their hopes of catching the attacker on the recovered DNA sample.
• January 2009: Robert Graham arrested for drink-driving in Hampshire.
• February 2009: Graham is traced to Australia.
• September 2010: Graham is arrested in Australia and extradition proceedings get under way.
• November 17, 2011: Graham is convicted of attempted murder.