Is there a ‘right’ way to deal with children who commit crimes?

How does an 11-year-old boy end up alone in a London police cell? Eleven years old, for heaven’s sake. That means either still in primary school, or at best in the nervous beginnings of secondary. Eleven still says muddy knees, flapping around in a blazer several sizes too big, and wanting a bedtime story – or at least it does for the parents of the lucky children. Life is not like that for every 11-year-old, however, and it is the unlucky ones who are perhaps most likely to end up in the bowels of a police station. His solicitor didn’t say what he was accused of doing, when she posted on Twitter earlier this week that “no child should be in a cell. Period.” Her point was that a custody suite is no place for a kid that small, no matter what they might have done.

But the mind makes leaps, anyway. Children as young as nine have been found carrying knives. Gangs organising so-called “county lines” operations, running drugs from the inner city deep out into rural towns, have been known to recruit from primary schools.

I thought about this boy, and what he might or might not have done, when the storm broke over a new film about the murder of toddler James Bulger. Vincent Lambe’s Detainment tells that painful story over again but this time through the transcribed police interviews and court testimony of Jon Venables and Robert Thompson, voiced by child actors. The boys had just turned 11 when they stood trial for his death.

Even a quarter of a century later, all this evokes disturbing feelings. Close your eyes, and you may still be able to see the CCTV images shown night after night; a tiny boy, his hand trustingly in that of an older child, being led off to what we now understand will be his death. His poor mother, Denise, had lost sight of him only for a moment in a busy shopping centre, yet by the time she began frantically searching it was too late. A nation was gripped by every unbearable moment of the trial, which to this day drives debate both about the possibilities and limits of rehabilitation – Venables has twice been jailed for offences involving child abuse images since being paroled in 2001, while Thompson is still living under his new identity – and about the social conditions that could have produced such horror. It feels like part of our collective national experience, and yet James does not belong to us. The memory of a dead child belongs first and foremost to his parents, as Lambe apparently failed to appreciate when he did not speak in advance to the Bulger family.

When Detainment was this week nominated for an Oscar in the best live-action short film category, a title that in this context sounds hideously crass, the family were understandably angry and distressed. Regardless of the artistic merits of the film, there is something grotesque about placing their dead boy in this glitzy, superficial, red-carpeted context.

But that is not their only objection. Friends of the family say they see the film as part of a wider liberal agenda to build sympathy for Venables and Thompson, pushing the memory of their son to one side. They want the focus to stay on James, as for them it always will be. And that is where things get murkier. It would be grossly unfair to demand that the Bulger family see their son’s murderers in any one particular light, but grieving relatives do not ultimately have a veto on how the rest of society engages with difficult moral questions.

Both Venables and Thompson were said to have been loved but neglected, raised by families struggling with addiction and mental health issues. They were perpetrators and victims of violence, at times both frightened and frightening. The trailers for Detainment – which is not on cinema release, but is being shown at film festivals – show the boys weeping and panicking in their police interviews, but Lambe says his film is a factual rather than a sympathetic portrayal, which does not seek to make excuses for them. It is right, he says, that we see them as human beings not monsters; children whose actions need to be explored and understood to prevent such things happening again. It is a crucial and timeless argument and yet the timelessness, in a sense, is the problem. To rake over all this again, with the pain it invariably causes, seems justified only if there is something new to say.

For the argument in favour of understanding is almost as old as the crime itself. It was most bravely made at the height of the trial, when feelings were running high on Merseyside and crowds tried to attack police vans bringing the boys to court. But it has been made sporadically ever since on film, in print, in books such as Blake Morrison’s troubling As If. The disturbing juxtaposition of childishness and murder is brought alive in the film by a shot of one of the boys sitting in a chair, small feet swinging inches from the floor. But it was captured at the time in court artists’ sketches and trial reports noting how Thompson sucked his thumb in the dock. The unanswered question hanging over Lambe’s film is why now, and why this story of all true stories? If the point was to introduce a new generation to the argument, then why not through the stories of that generation, fictionalised if necessary to avoid intrusion?

This week’s story of the 11-year-old languishing in the police cell turned out, in the end, to be both more and less troubling than it initially appeared. The boy’s solicitor, Kerry Hudson, confirmed later that the child concerned was accused of malicious communications over social media – not a trivial offence, given the impact of cyberbullying on vulnerable teenagers and the way gang violence often escalates from social media beefs, but not the most serious either – and was later released. The question of how the criminal justice system should approach children of this age committing un-childlike crimes, however, lingers.

Every time a teenager stabs another teenager on the way home from school, we are confronted all over again with the terrifying capacity of some children for violence and with questions about the social conditions in which that can happen. Every time, public opinion divides between those seeking to understand why a child carries a knife, and those who (as John Major said of the Bulger case) want to understand a little less and condemn a little more.

Yet as the children’s commissioner, Anne Longfield, has tirelessly argued, the process of gang recruitment looks increasingly like a form of grooming. Older boys, still children themselves, target younger ones who don’t see them as a threat. They single out the kids excluded from school, troubled, or hungry for attention they don’t get at home. Before long, these children, too, can become perpetrators and victims, both frightened and frightening. We may wait rather longer, however, for the film that imprints their stories as deeply on the national consciousness.