Picking through the debris of Columbine, experts from universities, government, and even the Secret Service have given their advice about how to respond to a potential repeat.

Few, however, have combined these valuable recommendations with the evidence about what helps prevent young people from becoming aggressive in the first place.

Speaking at the Social Research Unit’s Annual Lecture, Del Elliott, director of the Center for the Study and Prevention of Violence at the University of Colorado, spoke about his experience in the aftermath of the Columbine massacre.

Elliot described the knee-jerk reactions to crises, and how they rarely led to better outcomes.

After the Columbine disaster many schools responded with ‘target hardening’, for example, installing metal detectors.

“We are turning some of our schools into fortresses”, he remarked. “That is not healthy for children’s development”.

He explained how, in the Virginia Tech shooting security measures had actually left students at the mercy of the killer. An automatic ‘lock-down’ had sealed the doors to all the classrooms. Whilst the gunman shot his way through, the rest of the students were trapped.

A better response, observed Elliott, is to focus on building a safe school environment, characterized by clear, fairly enforced discipline policies and respect from teachers and peers. But how can this be done?

Part of the task, he suggested, is to break the code of silence in schools. Parents, children and teachers need to be able to share information about violent incidents or people who pose a real threat. In over 80% of violent incidents, someone knows it is about to happen.

Back in Colorado, Elliot has worked to help schools develop effective intelligence systems, including the anonymous Safe 2 Tell telephone hotline.

Children are able to report classmates who they are worried about. Information they receive is forwarded immediately to school officials and local law enforcement agencies who assess the threat and decide if and how to intervene.

In the five-year period to April 2009 the hotline received over 5,000 calls, leading to the prevention of 28 planned school attacks. But, Elliott explained, it’s not just that the hotline is there.

The team behind the hotline visit schools and talk to them about the ‘code of silence’ which stops students giving vital information about their classmates. They try to help them understand how children might be encouraged to use it.

Another contribution to creating safe schools is implementing evidence-based programs. Elliot and his team have assembled Blueprints, a database of programs that meet stringent quality thresholds.

These include a randomized controlled trial evaluation, sustained impact and replications in different settings.

Elliott ended his lecture by asking whether, $10 billion and a decade later, schools in the US are safer? Most of the money has gone into hardware, like the metal detectors.

There has been a slight fall over the 10 years in the number of young people carrying a gun, but still five per cent of students have done so in the last three years. On almost every other indicator of school violence Elliott’s sobering assessment was “no change, no change, no change”.

Why is this? According to Elliott, lessons from Columbine for responding to a violent incident in schools are now widely applied but effective strategies and evidence-based prevention programs are not. The lessons need combining.

One reason for this, he suggested, is that that academic performance is considered more important than violence prevention. “School leaders don’t seem to realize that children feeling safe correlates highly with good test results.

“There is also still a lot of confusion about standards of evidence, so people think they are implementing an evidence-based program when in fact they are not. They don’t know which list to turn to.

“Then there are the perennial problems of politics and parochial judgment trumping research, and the failure to implement programs with fidelity.

“America is not necessarily a good model”, he concluded, “but hopefully it provides some encouragement in your work here in the UK.”