When the convicted murderer spoke to his press agent for the first time last Wednesday morning, the gulf between them was so comically, luridly pronounced it could have come straight from the pages of fiction. While Kenny Richey stared at the nicotine-yellow walls of death row, Max Clifford was enjoying breakfast in Puerto Banus harbour, watching the yachts of oil billionaires bob in the Mediterranean sunlight. Richey is diabetic and lives on a diet of biscuits; Clifford was having scrambled eggs on toast.

If all goes to plan, things should even up some time in September when Richey arrives in Clifford’s London office after 18 years in the Mansfield Correctional Institution. Last month the sixth circuit court of appeals in Cincinnati ruled that the state of Ohio must release Richey or retry him for his crimes: the alleged murder of two-year-old Cynthia Collins in a fire intended, said the prosecution, to kill her mother, Richey’s former girlfriend.

The decree marked the beginning of the end of Edinburgh-raised Richey’s 18-year odyssey through the American legal system, a journey that has been nasty and brutal.

A recent breakout attempt in the jail resulted in prisoners having their telephone privileges reduced, meaning Richey’s only contact with Clifford was their chat last week.

But Clifford’s recently announced attachment to Richey’s cause is a curious intrusion of glamour into a campaign for justice that’s been grim.

The puffy, manacled Scot in his orange boiler suit, jaundiced from spending 23 hours a day in his cell, is an ill-fitting addition to the clientele Clifford usually represents. You name them and Clifford has booked the hotel suite where they sobbed their story in the direction of Lunchtime O’Booze’s tape recorder: Rebecca Loos, Tony Martin, John Leslie, Mandy Allwood and a thousand others. So why add Richey? “I’m not just about showbusiness,” Clifford says. “I deal in global stories about the high and low of society. The common denominator among all my clients is that they’re about to be thrust into the spotlight. That’s very much the case with Kenny, on a worldwide scale.”

And because he was asked, says Clifford, by Karen Torley, Richey’s fiancée. Having been “freaked out” by the scale of media interest when Richey’s potential release was announced in May, Torley, of Cambuslang, outside Glasgow, decided she could no longer act as a one-woman band.

“I was descended on,” she says. “That kind of thing won’t be good for Kenny when he’s out. He’ll be too fragile, he won’t be able to make any big decisions. But Max will be there to make them for him.”

As a client, Clifford says, Richey appealed because his 18 years on death row are certain to contain the PR man’s favourite journalistic quantity. “Stories within stories,” he says. “That’s what makes the ideal client. I mean, I don’t know what those stories are yet, I won’t know that until I speak to Kenny.

“But you have to figure that such a length of time in such a place will breed a great number of lines to pursue. The behind-the-scenes stuff, his relationship with Karen, all the times he came within a whisker of being executed. There’s a lot to be said.”

Already, says Clifford, requests are coming into his office for access to Richey after his release, including two television documentaries charting his readjustment to life on the outside. Clifford will take his customary 20%, although he is aware that Richey’s tale contains an inherent limitation in its marketability. “The way I see it, Kenny’s story is for the British market mainly,” he says. “The Americans don’t like being reminded they might have got something wrong.”

Richey’s supporters maintain the mistakes began in 1981, when the 18-year-old left Edinburgh to live with his American father in Ohio.

In June 1986, seven days before he was due to return to Scotland, Richey was arrested for Collins’s murder.

Eleven years later, a decade after Richey had been placed on death row, his defence submitted definitive new evidence demonstrating, it believed, that his conviction had been unsafe.

The prosecution did not argue the accuracy of the information but cited the US constitution to show that inadvertently incorrect forensic evidence did not justify a fresh hearing. Things were at stalemate until a series of appeals last year were upheld earlier this month in Cleveland, paving the way for a release in the autumn.

Given that Ohio has shown considerable persistence in its attempt to execute Richey, and that his brother Tom is serving 65 years for the murder of a shop assistant in Washington DC, what persuades Clifford of his innocence? “Because of what has happened in the past few weeks,” he says. “This type of backing down doesn’t happen very often in the States. The evidence is that Kenny’s arm was in a cast at the time he was supposed to be scaling the side of a building, and that the girl had been seen by two witnesses playing with matches. It was a complicated case and the truth took some time to come out. But I accept the court’s decision that Kenny was innocent.”

Does Kenneth J Parsigian, Richey’s lawyer, believe that Clifford is the right man to represent the client he has spent more than a decade attempting to clear? “We don’t pay for news stories the way you do over there, so I’m no expert on the practice,” he says. “Kenny has been wrongfully on death row for almost 19 years and he won’t be compensated. He has no immediate prospect of employment. He’s undoubtedly looking for someone who can get him a stake with which to start his life over.

“I really don’t know whether Clifford is that guy, but if he gets great financial deals for people who are involved in sex scandals, perhaps he can do even better for a falsely convicted man.”

“I’ve been dealing with the media for years now,” says Torley, “but the initial announcement about Kenny in January was a nightmare I can’t go through it again. So Max will be our protector. We hope.”

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