Barry and Margaret Mizen lost their son Jimmy four years ago. He was only 16 when he was murdered by a 19-year-old during an unprovoked attack in a bakery in Lee, southeast London. It was a senseless crime that shocked the nation.

But the horrific nature of the attack is not the only reason that the crime is remembered. Almost the whole country, it seemed, was moved by the quiet dignity of Jimmy’s parents. In the immediate aftermath they spoke eloquently of their grief and love for their son, and about how their Christian faith allowed them to feel empathy for the family of Jake Fahri, who was convicted of Jimmy’s murder.

They called for peace and forgiveness, not retaliation, and then they asked a listening Britain to make society more safe, courteous and fair. These seemingly instinctive remarks - and the courage the Mizens showed at a time of great pain - meant that the horrific crime has had a positive legacy.

Barry and Margaret, devout Catholics and parents to eight other children, have since become high-profile campaigners, called upon for their unique view of the criminal justice system as they set out to change young lives. The couple, who still live in southeast London, have visited more than 100 schools and pupil referral units throughout England in the years since their son’s death, speaking to thousands of children about violence and the consequences of crime.

Their close working relationship with the nation’s schools started just a few months after Jimmy’s death, when a friend who worked as a school chaplain at St Michael’s Catholic College in Bermondsey, southeast London, asked them to come in and tell their story. Neither had done anything like it before, but both admit that they have since “grown” into their new role.

“We are so fired up to want to do things for Jimmy. We want to do it; we feel like we have something to say,” Barry says. They are determined to get their message across: “A peaceful response will bring about change.”

When they are with pupils, Barry and Margaret first explain what happened to Jimmy and share pictures of their son. They stress the importance of caring for one another. Children respond to the Mizens’ message, often listening in rapt silence. But pupils can and do ask questions. Among the most frequent are how the couple managed to forgive, if they cry much and how their eight other children are coping. Sometimes pupils want to hug the couple, and many come up to them afterwards to try to express their sadness about Jimmy’s death.

After the sessions, teachers often comment that some of the children had initially complained about having to sit through “another” talk on knife crime.

“When they came in for the first time to speak to Year 11, they were phenomenal,” says Grainne Grabowski, head of St Michael’s. “They spoke calmly and quietly, but you could hear a pin drop because the impact of their story was so strong. They had a completely different approach and children were very touched by what they had to say.”

Barry and Margaret have since returned to St Michael’s several times; pupils recently made them a picture of Jimmy composed of individually decorated tiles. Speaking to the couple, it soon becomes clear that endlessly reliving the horrific events of May 2008 is not easy for them or their family, but they are determined to create something good in Jimmy’s name.

Before Jimmy’s death, neither of his parents “had spoken to half a dozen people” publicly. Now they have made speeches to thousands. The response to Jimmy’s case, Margaret says, has helped them to do this. “If you share something personal, it provides a safe place for another person to do the same; it allows them to open up.”

The Mizens’ campaign is not complicated. Nor is it revolutionary. They simply want children and teenagers to contribute to their community, to make it a safer, better place.

Care for the community

Through the Jimmy Mizen Foundation, the charity created for their work, they have encouraged teenagers to organise “100 days of peaceful events” to coincide with the Olympic and Paralympic Games. At the end of these 100 days, on 28 October, there will be a concert in London, with tickets given as a reward to children.

“We want to encourage young people to do something for their schools and local communities,” says Barry, who still works in the family shoe-repair business. “We find when they are given responsibility, they grab it with both hands and are excited by it. All of us have a responsibility towards our communities.”

Such work has made the Mizens household names and brought celebrity backers for their campaign. London Mayor Boris Johnson, broadcaster Dermot O’Leary, singer Stacey Solomon and the Saracens rugby team have signed a “Release the Peace” car, which is currently travelling around schools, spreading the message.

Another of the charity’s initiatives is the CitySafe Havens project. Launched in 2009, shops and local businesses pledge to report all crime and antisocial behaviour to the police, and offer their premises as a place of refuge for young people in immediate danger. More than 350 businesses are now part of the project. They also refuse to sell alcohol, knives or other dangerous items to underage or drunk customers.

In southeast London, pupils from Prendergast-Ladywell Fields College assessed for themselves which shops they would feel comfortable going to in an emergency. They then asked the shopkeepers to sign up to the CitySafe Havens scheme. Those that did were visited by police officers, who gave them advice and promised to respond promptly to their calls.

The school is now in awe of the Mizens. “They have been an inspiration and the children have achieved so much in responding to their message of working together to bring about peace in our community,” headteacher Mel Whitfield says. Indeed, as is evident from the CitySafe Havens project, the Mizens have put schools at the heart of their work.

“For some children, the only stability they have in life is at school,” says Barry.

The couple are insistent that discipline in schools should not be confrontational, and should instead be about firm guidelines. One of the most striking aspects of their involvement in schools is their grasp of the day-to-day details. They explain how early intervention, including “managed moves” of children to different schools, can benefit them.

“It is so important to catch children early on. If you speak to teachers, they are able to look at their class and make accurate judgements about which children have particular problems,” Barry adds.

The Mizens feel Jake Fahri’s problems should have been spotted sooner. Instead they built up “little by little” and he ended up taking their son’s life. For this reason, the Mizens also visit adult jails and young offender institutions.

“So many people stay locked up for life. We say we should prevent them from getting there. Society should be ashamed by the number of young people who get to that situation and have ended up committing horrendous crimes,” Margaret says.

Rather astonishingly, Barry adds that “children in these situations (often) have a lot of natural leadership. We should help them use their skills for something positive rather than negative.” It is this kind of extraordinary observation - and their determination to see the best in some of society’s worst - that makes the Mizens remarkable.

Following Jimmy’s death, his parents made a pact not to cry in public because they “don’t want people’s pity”.

“We can scream and shout but it won’t bring anybody back,” says Margaret, quietly. But in their work, they make a very real difference to those who are still alive.

For some children, the only stability they have in life is at school.