Robert Graham said he acted as a Good Samaritan and intervened when Leslie Cumming was being beaten by another man.
“I did not assault him. I stopped him getting a bigger hiding than he got,” he claimed.
The High Court in Edinburgh has heard Mr Cumming, 68, was deputy chief executive of the Law Society of Scotland when attacked on 23 January, 2006, in a lane at the rear of his Murrayfield home. He was slashed and stabbed in the face and body.
Graham, 46, said he was born Paul Francis McGhee in Dublin and moved to New Zealand aged nine. He came to the UK in 1999, using the name Robert Leiper Graham and a false date of birth. He had a New Zealand passport “dishonestly obtained”.
In Scotland, he met a woman and had three children but said he never told her his real name. Graham said he wanted a UK passport believing it would have helped him secure well-paid work abroad, and it was during his efforts to illegally obtain a passport that he came across Mr Cumming.
Graham was in contact with a man known as “the facilitator”, and let it be known he was willing to pay £3,000 for a passport and driving licence.
He arranged to meet the facilitator in a pub in Leith, but later learned somebody else would attend. Graham told the court he met “Gogs” who told him they were going to meet the man providing the documents. They drove to Murrayfield and walked into a lane. It was dark when a car arrived. Graham now knew the motorist was Mr Cumming. “I was told that will be him, and Gogs walked off towards him. I was to wait until he called me. I presumed he was going to organise the introductions and call me down,” said Graham.
“The next thing I remember hearing was Gogs yelling out, calling Mr Cumming a ‘f****** beast’. That was when he set about him.”
Graham said there was enough light to see two silhouettes struggling and fighting. “I started to walk towards what was going on. I should have run the other way. I did not really know what was happening. With the benefit of hindsight, I would have run a mile in the opposite direction.”
Graham said he could see Mr Cumming on his knees.
“I did not see a knife, ever. I grabbed Gogs from behind and pulled him off. Mr Cumming had a hold of my leg, trying to pull himself off the ground. I pulled him by the arms and started to help him up and he started attacking me. He got up fighting. He was still fighting for his life, a frenzied flailing of his arms out in front of him,” said Graham.
“I broke free from him … I saw Gogs was not there… I ran. At the end of the path, I was confronted by a headbutt. It was Gogs. He got into his car and shot off.”
Graham said he went home and called “the facilitator”. He was warned to keep his mouth shut or face the same.
A former workmate has alleged Graham confessed that he had “done a judge in” and been paid £10,000. He denied the claim. Prosecutor, Lesley Thomson, QC, put it to Graham that his account had been fabricated.
“I refute that,” he replied.
The trial continues.