Jonathan zito died 10 years ago this year, but to his wife Jayne it still feels much more recent: "We have just had some flyers printed for our autumn conference and they've used John's picture on the front - he looks so young on it and I've just realised how old I'm getting really," she says throwing me a sad smile.

Twenty-seven year old Jonathan's death generated national headlines when he was murdered on a train platform on the London Underground by Christopher Clunis. Stabbed just above his eye, Jonathan died of a massive brain haemorrhage.

The police did not have to go looking for the assailant as Clunis made no attempt to leave the scene of the crime. "When the police came for him, he said 'I've killed somebody haven't I?'," recalls Jayne. "So there was no need for any kind of investigation, to look for an offender - as soon as he was interviewed it was apparent that he was ill."

Jayne says that she realised straight away that Clunis was ill, not least because the attack on Jonathan was unprovoked. "I remember the police coming round and saying that Clunis lived in a bedsit in north London, and they had found lots of medication and tablets in his draw - his flat was full of untaken tablets. Obviously he was ill. But what kind of history he had, we didn't know until his trial."

Driven by "a want of the best for Jon", Jayne initially began campaigning to get an inquiry into Jon's death and Clunis' care - particularly because it came to light during the Old Bailey trial that he had an eight-year history of failed psychiatric care. The Judge ruled that Clunis be held indefinitely in a top security mental hospital.

"He'd been in and out of psychiatric hospital, he'd had a documented fascination with knives," she recalls. Jayne had her own professional experience in mental health - working as a deputy manager at a Rehab Hostel with people recovering from mental health problems - and "alarm bells" started to ring: "I realised that he hadn't been treated. I'd worked with individuals who were either a risk to themselves, or to other people, so I understood the processes of supervision, service provision and the communication that needed to be in place in the network to enable a patient to support themselves, and for other people to support them, in the community."

Jayne's job involved counselling young people - through "talking therapy" - who had just come out of hospital and were reliant on medication. Jayne was frequent witness to the side effects of these drugs: "One young man suffered terrible tremors," she recalls. She did a research report on the effects of medication for a management course. "I used to give presentations once a week to the residents on the medication they were taking. The side-effects were quite far-reaching, and had consequences for breast feeding and pregnancy and the sex drive. There was a lot of fear amongst the residents concerning the impact of their medication," she says. "But also a lot of fear as to what would happen to them if they stopped taking it as well, because the illness had been so frightening for them."

Staff were dependent on outside services - especially if patients relapsed quickly. One day a young man killed himself when Jayne was on duty. "It was terrible," she recalls. A patient in a voluntary hospital, he had discharged himself and turned-up at the hostel. Obviously deeply disturbed, Jayne realised that she did not have the experience to deal with him. So acting on advice she rang the hospital for help: "I asked them to please come and do an assessment because he shouldn't be there and he'd walked out of hospital. But they said that he wasn't ill enough to be sectioned and he would have to stay with me and the other staff. By five o'clock that evening he was dead."

He had jumped off a bridge.

It was just such a failure by the authorities to actively intervene in the case of Christopher Clunis that led Jayne to campaign to bring the conclusions of the report - detailing the paucity of care that Clunis received - into the wider arena.

"I got so much media attention at the beginning because I said: 'Jonathan is a victim and Christopher Clunis is a victim.' And that is still the message of the trust." Jayne began to receive mail from other members of the public telling her their stories, from sons who had committed suicide to daughters who had been murdered by other patients.

"I decided that a service needed to be set-up to respond to people in need like myself, because nobody supported me when Jon died apart from my family and the police. Nobody from the health authority or the victim trust came forward and offered any support whatsoever," she says. "You are very isolated when you have been bereaved in this way." And so, in partnership with Michael Howlett, the Zito Trust was formed, a support service for victims of failures of care in the community, offering advocacy and advice.

"What we see in the Zito Trust is a reluctance to acknowledge risk and violence and the needs of other people to be protected", she says. The Zito Trust has been criticised because of its focus on violence: that because so much public attention is focused on issues to do with risk, policy is being unfairly skewed towards compulsion rather than holistic treatment.

"But I don't actually agree with that," she says. "The answer is holistic treatment but an acknowledgement that compulsion needs to take place, and that people have a right to be compulsorily treated." Clunis, she says, had a right to be compulsorily treated against his will. "My patient had a right to be compulsorily treated to stop him jumping off a bridge. He would still be alive."

This, she says, raises a fundamental question: should we force patients to take medication that gives them side-effects? Especially if they stop taking them and risk relapse and hurting themselves or other people. "It is quite a philosophical argument isn't it? It is about the rights of individuals - about the right of a mother not to be killed by her son versus the right of her son not to take his medication. It is a choice, a choice of liberty."

Last year the Zito Trust published a report, The Practice Gap in Schizophrenia: are people with a mental illness being given the best chance in life? which contained a map showing the prescribing rates for atypicals by constituency (see above).

The average prescribing rate for atypicals is 18 per cent but the map shows that the rate varies enormously from one part of the UK to another.

This is why, she says, it is so important that NICE gives its approval to atypical medication. "We all want choice, we all want information, and we all want what's best. That would encourage patients to take their treatment, and it would give people a better quality of life."

Jayne Zito is the founder of the Zito Trust which campaigns for improvement in community care for the mentally ill