Mr Hussain has expressed sympathy for his victim's family
A Leeds man has spoken out for the first time about spending 18 years on death row in Pakistan.
Mirza Tahir Hussain, 36, was freed this month and returned to the UK after Pakistani president Pervez Musharraf commuted his sentence.
He was convicted in 1988 of murdering taxi-driver Jamshed Khan but always said the killing was in self-defence.
He told the BBC Asian Network Mr Khan had produced a gun. In the "ensuing scuffle the gun suddenly went off".
He also expressed sympathy for Mr Khan's family.
Mr Hussain is staying in a secret location in the north of England while he adjusts to life outside of prison.
In the interview Mr Hussain explained how during a taxi journey from Rawalpindi, Mr Khan had pulled a gun on him and demanded valuables, and a struggle ensued.
"At the point where the gun was not aiming at me, I went for the gun and grabbed his wrist and in that ensuing scuffle the gun suddenly went off," he said.
"The gun was still in his hand, so I was trying to snatch it from him and there must have been some kind of pressure on the trigger."
Mr Hussain said he did not feel guilty about the incident but had felt "duty bound" to report it to the police and get medical help for Mr Khan.
But he claimed the police then tried to fix the case against him.
Mr Hussain's prison cell was just 10ft from the gallows
When he was arrested, Mr Hussain said neither he nor his family had known what his legal rights were or who they should contact for help.
He said he was "very humbled" by the intervention of Prince Charles in his case, but that it "might have made a great difference" if the government and Foreign Office had intervened in the initial stages of the case 18 years ago.
"I might have been released there and then," he said.
Instead, Mr Hussain found himself confined to a 12ft by 9ft prison cell just yards from the gallows which he faced being sent to for many years.
The cell had a raised platform for a bed and a small, "really smelly" toilet in the corner.
Prisoners were taken from the cell, straight to the gallows 10ft away, with just a day's notice.
"We [could] hear the guards and all the officials gathering for this purpose, and when the inmate is made to stand on the trapdoor.
"And when the trapdoor opened we [knew] somebody had just been hanged."
Mr Hussain said he would now try to help others in the Pakistan prison system, many of whom he believes are innocent.
He said he felt sympathy for Mr Khan's mother, who is furious about the decision to release him.
Mr Khan's family have said they plan to appeal against the decision to commute Mr Hussain's sentence.
Mr Hussain said: "As a Muslim I mean, I cannot reverse all this, but I can understand how it feels.
"I'm sorry for her son's death in such circumstances and in that way."
Mr Hussain said facing his own family on his return to the UK had been very difficult.
"Because of our religion and culture, such incidents are seen as very shameful and horrible," he said.
"We are brought up in such a way that we just cannot imagine harming or killing someone.
"It is very difficult for me to come to terms (with that) or face my family."