For the third summer in a row the arrival of the holidays has been accompanied by gruelling, grisly coverage in all media of a child's murder, probably by a paedophile.

Parents are understandably very concerned by the story. Their kids are charging about enjoying the sunshine (at least today) and freedom from teachers. How could I live with myself, they wonder, if something happened?

This is what is so hideous for a parent of a murdered child - almost whatever the circumstances, the parent is bound to find some way in which they could have prevented it happening and therefore, is bound to be plagued with guilt, in most cases for the rest of their lives.

The trouble with all this is that, although it is a hideous prospect, it is utterly absurd for parents to be worrying about the safety of their children. They are at no greater danger than they have ever been in recent times.

The only reason that they are worrying so is because the tabloids, followed sheepishly by the broadcast media, have realised that playing on parents' fears sells newspapers. For the unforgivably hypocritical likes of the Daily Mail, who make themselves out to be concerned about families and piously against crime, this story is a cynical method for increasing circulation.

The reality of child murder is as follows. About 80 children are murdered every year. Of these, an average of just seven are killed by someone with whom they were not previously acquainted. The vast majority of victims are killed by their parents and of these, the majority have a low income.

If the Daily Mail really wanted to draw attention to an important social problem they would focus on this latter: the fact that one quarter of children are still being raised in low-income homes as a result of the economic policies of the Mrs Thatcher that the Mail so vigorously supported.

But that is hardly likely to be their focus. Instead, they devote huge space and energy to turning a real life horror story into an episode of Cracker or Inspector Morse. For the awful truth is that there is a huge market for these ghastly stories because we, including me and including you, are completely gripped by the unfolding saga. We do want to hear the perverse detail that Sarah was found naked, that the murderer seems to have customised his van for committing the crime and so on. We do pay attention as the narrative is unpacked for us.

It begins with the child going missing. Then the parents are wheeled out to express their concern. Small clues emerge... Sarah last seen by sibling... man with white van seen nearby... police widening search, and so on. It becomes obvious that the child is dead and we find ourselves, mostly unconsciously, identifying with what it would be like to be sexually abused and murdered as a child, what it would be like to be living with the likelihood that this has happened to our child. And we do find this entertaining, just as we enjoy horror movies or crime fiction.

But most worrying of all, I believe we also must be identifying with what it would be like to be the perpetrator of this crime, if nothing else, at the level of being the man who is calling all the shots, leading the police a merry dance.

The awful truth is that we are fascinated and excited by these crimes. That is the only possible explanation for the massive and unrelenting success of the innumerable TV dramas which use these plotlines.

But the fact that humans are base and vile is no excuse for the annual charade of the child murder that is now played out every summer. We have to be protected from ourselves and it is most nauseating of all to see the Mail and its brethren both pretending to follow these stories in the public interest and actually using them to sustain sales.

One solution would be for them to exercise restraint but that is like expecting a paedophile to stop his perversions voluntarily. Paul Dacre (the Mail's sanctimonious editor) and Lynda Lee Potter must get their daily fix of nastiness dressed up as public interest.

The only hope is for government to control this more directly through the press regulator and by stopping the police from mounting an obscene annual show. There is absolutely no need to give so much detail: why do we have to be told whether the victim was fully clothed or not? Why are we informed that the parents were not allowed to see the body (implying it had been deformed)?

If the Mail were even slightly sincere in its claims of public interest, it would focus on the real dangers for children: of asthma, caused by 20 years of Mail-backed Tory failure to curb car use; of grossly unhealthy diets, leading to overweight children who will become heart attack victims in adulthood; above all, of having parents on a low income.

But the Mail cares nothing about these things. Far better to flog lots of copies by titillating us and terrifying parents with the story of the sexual murder of a small child.

• Oliver James is a clinical psycologist and author of Britain on the Couch: why we're unhappier compared with 1950 despite being richer
Buy Oliver James's book on BOL