Hugh Callaghan dies aged 93: The day Callaghan convinced E&S man Rhodes that he might be innocent

And now he found himself sat in a bleak prison room, face to face with Hugh Callaghan, one of the men convicted of killing 21 people, and injuring 182 others.

And Peter Rhodes, an award-winning writer for the Express & Star, wrote how the meeting left him convinced Callaghan might actually be innocent.

Callaghan, who served more than 16 years in jail after being wrongly convicted of the bombings, has died at a hospital in London aged 93.

Rhodes met Callaghan in the grim surroundings of Long Lartin prison, near Evesham, in June 1990.

At the time, the Birmingham Six – Callaghan, Paddy Hill, Gerard Hunter, Richard McIlkenny, Billy Power and John Walker –were trying for a third time to get their convictions for the Pub Bombings overturned.

Their prospects did not look great. Their initials application for leave to appeal was dismissed in 1976, the year after their conviction. Investigations during the mid-1980s by Granada television reporter Chris Mullin cast doubts on the men's guilt, but these were largely dismissed as what would today be called conspiracy theory. They were finally granted leave to appeal in 1987, but the convictions were upheld in January 1988 following a six-week trial.

The following year the Guildford Four ­– convicted of IRA pub bombings in Surrey in 1975 – were cleared by the court of appeal after a long campaign by Mullin, who was by this time a Labour MP. Rhodes interviewed Mullin, who told him he knew the Birmingham Six were innocent because he had spoken to some of the real perpetrators. He also said some of the police officers who worked on the case had admitted to getting it wrong.

Up until this time, Mullins had largely been dismissed as something of an eccentric, but Rhodes said the Express & Star was one of the first papers to take him seriously.

Nevertheless, Rhodes was at this point unconvinced. Shortly before his meeting with Callaghan, he wrote a column re-stating the evidence against the Six.

"It seemed powerful," he recalls.

"Hughie took it badly and got in touch and asked me to visit him in prison which I did, a few weeks later."

During the interview at the maximum-security jail, Callaghan described the moment he was charged, and told that other people had implicated him in their statements.

"This one officer was a raving lunatic," he told Rhodes.

"He said, 'are you going to make a statement or are you going to get bounced around these walls?'"

Callaghan said he told the officer he had an ulcer, and was getting pains in his stomach.

"I asked them for milk and biscuits but they gave me nothing," he said.

"I told them I was a nervous individual and they played on that.

"They left the cell door open all night and a policeman sat outside, clicking a gun.

"There was an alsatian dog roaming about the cell. The handler said, 'I've only to say bite and he'll bite'. I didn't sleep.''

Unlike the rest of the Six, Callaghan never claimed to have been severely beaten by the police, but told Rhodes that he was subjected to psychological torment that was worse than physical violence.

Like the rest, Callaghan said he was beaten up by warders at Winson Green prison – 14 prison officers were later cleared of assault.

He insisted he never had any links to the IRA.

Paradoxically, he told Rhodes that he thought the release of the Guildford Four – and an inquiry into the convictions of the Maguire Seven, who would also later be released ­– would actually count against him and the other five. He said that with so many cases collapsing, the establishment would fight to preserve the Birmingham convictions.

"I am not a bitter man and I try not to get depressed," he told Rhodes. "You just have to snap out of it.

"We are able to cope because we have a clear conscience. We haven't hurt anybody. We haven't planted any bombs. We are not members of the IRA. We do not lose any sleep.''

At the time of the interview, there were hints that the Six might soon be offered parole, but Callaghan said if that were the case, he would turn it down.

"We are innocent," he told Rhodes. "I want to see my family. I want to see the countryside. I love the nice things in life. But we will not be quietly slipped out of the back door.

"I feel so sorry for the people in those two pubs. But what about us. We are also victims of the Birmingham Bombers."

Rhodes observed that in 1974, few doubted the word of the police against IRA suspects. But the collapse of the Guildford Four's convictions, and the West Midlands Serious Crimes Squad being disbanded for fabricating evidence, that certainty could no longer be taken for granted.

Rhodes concluded: "For what it is worth, my opinion is that an IRA cell capable of planting the dozens of bombs which caused so much terror in 1974 would not have recruited the man I met in Long Lartin. A nervous 44-year-old with an ulcer is a liability."

He said of the Six, Callaghan always looked the least likely mass murderer. But he added that it was central to both the defence and prosecution cases that the Six were together on the evening the bombs were planted.

"Either all are as guilty as sin, in which case justice has been done, or all are innocent, in which case we are contemplating the most appalling and shameful miscarriage of justice," Rhodes wrote.

"And I have this awful, creeping suspicion that Hugh Callaghan is innocent."