Andy Coghlan reports on programs trying to stem killings by changing the societal understanding of violence:

Shootings and killings in deprived areas of Chicago and Baltimore have plummeted by between 41 and 73 per cent thanks to a programme that treats violence as if it is an infectious disease...The most important but controversial element of the programme to tackle the epidemic of violence is sending reformed shooters out into the streets as mediators in disputes and mentors for youths.

"At age 17 I'd been arrested several times and convicted of four gun-related offences," says Jalon Arthur, a key violence interruptor speaking in a teleconference on 30 June. "You must work with the shooters, and credible messengers like me need to understand the minds of the perpetrators and have the measure of street-credibility to overcome mistrust," said Arthur.

"For individuals who engage in gun activity, there's a great deal of paranoia which makes them very difficult to influence, but because violence interruptors have been through the transition themselves, they have the social networks and enough street cred to reach these people," said Arthur.

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