The chilling violence involving guns and knives has dominated the headlines, yet many cases go unreported. In a new tactic, police rely on hospitals and schools to help monitor the hidden victims.
By Mukul Devichand
Producer, The Investigation
Recent stabbings of teenagers have shocked the nation and much attention has focused on London's black community.
But it is police in Glasgow who face Britain's most stubborn problems with gangs and youth violence.
Teenagers from the Real Calton Tong gang say they cannot even walk to new sport facilities nearby, for fear of crossing gang lines and being stabbed. One displayed a recent knife wound on his scalp, inflicted the same night.
Police are often in the dark about gang-fighting like this because it isn't reported to them.
Knife attacks have made headlines in recent years
"We don't understand the problem, because only a third of violence is reported to us," says Detective Chief Superintendent John Carnochan, head of Strathclyde Police's new Violence Reduction Unit.
He is a murder detective with 30 years of experience, but believes the police need to get much smarter about how they tackle violent behaviour.
Traditional police tactics like stop and search, knife amnesties and harsher sentencing have failed to tackle the root of the problem, he says.
Instead, Strathclyde Police are using a new approach originally developed by the World Health Organisation in countries like Colombia and Jamaica, which relies on hospitals to provide intelligence.
"It's very frustrating to see people coming in week after week, year after year, with very serious injuries and sometimes fatal injuries," says Rudy Crawford, an A&E consultant at Glasgow Royal Infirmary. "To me, it is a form of disease."
Dr Crawford's staff are now recording important details about violent incidents from those who come to them with injuries, and passing the information on to the police.
The data doesn't identify the patient. But it allows the police to understand how, where and why violent incidents occur in much more detail - so the police can understand better when to stop people, and where to assign officers.
Have amnesties worked?
Like other forces across the UK, Strathclyde has assigned several officers to be based full-time at secondary schools, where they can develop relationships with children.
And it is hoped cognitive behavioural therapy for stab victims will help them identify and avoid the behaviour that led to them getting injured in the first place.
Gathering more sophisticated data about violence at hospitals could mean the levels of recorded crime go up, but
police say that's a price worth paying.
"A politician's never going to phone us up and say thanks very much, you've pushed up the crime figures," says John Carnochan of Strathclyde's Violence Reduction Unit. "But we've got to do it."
The idea of hospitals recording violent crime has now spread south of the border. One hospital in London has piloted the scheme and it will soon be extended across the capital, according to Det Chief Supt Chris McDonald, head of Operation Blunt, the knife cream taskforce at the Metropolitan Police.
"There is no question that there will be greater violence-against-the-person crime statistics than there are at the moment," he says. "But fine, let's get to know what is going on."
The Investigation: Knife Crime was broadcast on Thursday 3 May. It is available online for seven days at Radio 4's Listen again page.
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