What price 25 years?

Andy Evans was given ?100,000 as an interim compensation payment when he was first released from prison. After 25 years inside, it was an unimaginable sum. "I started spending money like mad," he says. "I would give cab drivers ?200 tips. I bought five computers - when one went wrong, I'd give it away and buy another. And my kitchen was full of God knows how many food blenders. If I couldn't be bothered to clean one or thought it was too loud, I'd get a replacement." He even bought himself 12 staple guns. "They were a status symbol inside - and hard to get hold of."

Today, two and a half years since walking free from Winson Green jail in Birmingham, Evans has "just the one" staple gun. He may have frittered away that early payout, but his money worries are probably behind him: 12 days ago he was awarded an extra ?750,000 by the Home Office. He's now received around ?1m, believed to be a record payment, but then Evans, now 45, served a record sentence: 25 years for a murder he did not commit, the longest anyone in this country has been imprisoned before being freed on appeal.

Evans' nightmare began one October morning in 1972 when - as "a crazy, mixed-up 17-year-old" - he walked into a Stoke-on-Trent police station and confessed to the murder of 14-year-old Judith Roberts.

"I didn't have any real friends and was a bit of a loner," he says. "I couldn't read or write properly, was taking valium for depression and waiting for a medical discharge from the army. I was also eaten up with guilt. Perfectly normal feelings towards the opposite sex played on my conscience. I was a mess." He says that a dream in which he saw "a hazy combination of images of women's faces" convinced him that he was responsible for the death of the local schoolgirl. "By confessing, I thought I'd be able to rid myself of all the crap going on in my head."

Judith's body had been found in a field only eight miles away from Whittington barracks, near Lichfield, where Evans was stationed. "When I woke up I decided to see the police and sort it out," he says. "I was living with my gran. When I told her what I planned to do, she told me not to be so bloody daft. When she fell asleep before lunch, I left the house." Evans was questioned for four days by the West Midlands serious crime squad, which has since been disbanded, without a solicitor or GP present. When he asked to see a photograph of Judith, he was told it would not help matters.

Then, due to a wretchedly improbable coincidence, he succeeded in providing details of the murder which detectives assumed could only be known to the killer. Six years before, Evans had been playing fireman's lift with a friend; the friend fell and suffered concussion. Evans still felt immense guilt about this and, in his confused state, told detectives Judith had sustained head injuries but had not been sexually assaulted, which the post mortem confirmed. The police thought they had their killer.

As his trial at Birmingham Crown Court approached, Evans "began to unravel everything in my head until I realised I hadn't done it. My confession, which the police helped me write, was a means of running away from myself. I retracted it."

At the time of the murder, Evans had been watching TV in barracks with another soldier, who had since been transferred to Germany. By chance, this soldier had the same name as a fellow soldier who had not seen Evans on the day of the murder - another fateful coincidence. Evans' solicitor interviewed the wrong soldier, leaving his alibi in ruins. With no eyewitnesses or medical evidence to link him directly to the murder, Evans was then given the now discredited "truth drug" brietal: "That really messed up me up and I thought I was on another planet."

Evans was sentenced to life. As a timid teenager labelled a child-killer, he found prison terrifying. "In the early days I was petrified," he says. "I tried to keep my head down, but it wasn't easy. When my conviction was reported on the news, I would be beaten up by other inmates. In fact, when any murder of a kid was on the television, I feared for my life. Staying alive was my only priority, as everyone inside thinks you're as guilty as sin."

At this point, Evans breaks down. "You learn to face facts, that this is it," he says. "You see the light die in people's eyes. You can spot the ones who will end up slitting their wrists, being raped or turning vicious." He takes a minute to compose himself. "You want to reach out, to help those who have spiritually died, but you can't. You can't appear weak."

He survived with the help of another inmate, also serving life for murder. "I nearly cracked up. I'd lost all hope. Some inmates would spit on my food and I'd still eat it. I didn't wash for weeks. Then this guy comes up to me and reminds me I'm human. He says he hates what I'm in there for and, whether I did it or not, it's my business. But of all the people inside, I'm the only one he'd like to meet outside. It might not sound impressive, but thanks to him I kept my sanity."

Many more years were to pass ("time doesn't crawl slowly, it grinds to a halt") before Evans gave any thought to appealing. But a chance meeting in 1993 with Steve Elsworth, a former Greenpeace member who was giving a lecture to inmates, was a turning point. "I happened to be chatting to him about my case," says Evans. "He told me he had friends in Amnesty International and promised to mention me. Over the next four years, the campaign for my release snowballed."

Kate Akester, of the human rights group Justice, took up Evans' case, as did the eminent Norwegian psychologist, Gisli Gudjonnson, whose research into false confession syndrome and interviews with Evans were to prove crucial. So he emerged from prison, in December 1997, a shattered man. He was completely out of step socially, the art of everyday chat beyond him. The bitterness in his voice is suddenly striking. "What had I to show for the last 25 years? Nothing. What had I done? Listened to too much screaming, that's what."

There are still bad days, and he receives trauma counselling. "The nightmares haven't stopped. I curl up into a ball and physically ache." But, slowly, he's made a life for himself. He met Sue, his "lovely wife", when she replied to an advertisement he placed at his newsagent for a cleaner. She seemed to vaguely recognise him, and he decided to show her the newspaper cuttings about his case. It was an oddly moving moment for both, one which created an immediate bond between two strangers. The two were married last month and are now looking forward to a honeymoon in the Caribbean, buying a house in Nottingham, and "having some fun".