As a child, I was friends with a twelve-year-old boy who attempted to murder a slightly older girl. They’d argued over which television programme to watch and he fetched a knife from the kitchen and thrust it deep into her back. Paul (not his real name) then left the room.

At first the girl thought that Paul had just punched her very hard. She felt ill and lay down on the settee on her stomach. When the pain intensified she looked back and saw the protruding handle of the knife.

The teenager staggered downstairs to alert a neighbour. Thankfully the neighbour left the weapon in situ – if she’d pulled it out, the girl would certainly have died. As it was, the blade had done irreversible damage to one of her lungs and she spent weeks in hospital, initially in intensive care. She later faced reconstructive surgery for the hole left in her back and had to take strong prescription drugs to help her sleep.

Twelve-year-old Paul now faced an attempted murder charge – but numerous adults came forward to say what a polite and helpful boy he was. He belonged to a youth organisation and they too were very impressed with him. The judge recommended that he see a psychiatrist and the parents said that they’d arrange this, but didn’t. His teenage victim was terrified that he’d attack her again.

It’s unclear how much the judge knew of Paul’s background – but I know that he and his siblings were regularly terrorised by their alcoholic father. He verbally mocked them and beat them with his belt. Paul’s mother did nothing to stop these sessions, instead adopting a slightly martyred tone and telling anyone who would listen that her children were very polite to strangers and that she couldn’t understand why they glared at her when they were at home.

In fairness, I really liked Paul’s parents and spent as much time as possible with them. Both had the capacity to be kind and generous to a child who wasn’t their own. Paul’s mother cooked me excellent meals and both parents took me with them on family outings, adventures I’d otherwise never have enjoyed. It was only in child-nurturing that they failed, presumably parenting as they had been parented.

Paul’s attempted murder charge was just one of numerous instances of violence in my childhood so it quickly faded from my consciousness. I rarely thought of it again until halfway through writing this book. Only then did I realise that Paul’s story had the same ingredients as almost every child’s story that you’ll find here. That is, the child is physically and emotionally abused by an adult or adults, often the very people that created him. In turn, he – or she – goes on to perpetrate violence on someone else.

The children in this book tortured, burnt, battered, strangled or raped their victims – victims aged from two years old to eighty. But these young killers had been tortured, burnt, battered, half strangled or raped before they carried out their pitiless acts.

The first two profiles are historic ones which demonstrate that children who kill aren’t a modern phenomenon brought about by horror videos or by single parent families. There are also brief details of other latter day killers in some of the sociological chapters, one of which bears a striking resemblance to the Robert Thompson and Jon Venables case.

The rest of the profiles are contemporary, featuring young killers from Britain and America whose ages range from ten to seventeen. But there are case studies in the later chapters involving younger children including a boy who killed at the age of three.

Several of the murders involve a sexual element, but as many readers find it difficult to understand how young children can become sexual predators, I’ve incorporated a chapter on youthful sex killers which offers many more case studies. These killers are male but some were sexually molested by their mothers so the chapter also looks at female sex offending, an under-reported crime.

These crimes are horrifying but comparatively rare. Though the media likes to suggest otherwise, there isn’t an epidemic of mini-murderers in Britain. To give some examples, in 1995 – 1996 there were 30 people under the age of eighteen convicted of murder in England and Wales. In 1996 – 1997 there were 19 and in 1997 – 1998 there were 13 such deaths. 1998 – 1999 saw 25 and the following year there were 23. These later numbers may rise as some cases are still being dealt with by the police and by the courts.

The numbers rise by approximately twenty convictions per year if we add manslaughter and infanticide to the murder statistics. But children are still far more sinned against than sinning when you consider that one child a week dies in Britain at its parent’s hands.

Moreover, the children who commit violent crimes have invariably been victimised by violent adults. A recent study of 200 serious juvenile offenders found that over 90% of them had suffered childhood trauma. 74% of the total sample had been physically, sexually and/or emotionally abused and over 30% had lost a significant person in their life to whom they were emotionally attached.

The following profiles, then, are stories of cruelty and of loss, of children who weren’t allowed to experience a happy childhood. But they can also be stories of hope because the power to change future childhoods is within our grasp.