interrupter
n.— «CeaseFire tries to deal with these quarrels on the front end. Hoddenbach’s job is to suss out smoldering disputes and to intervene before matters get out of hand. His job title is violence interrupter, a term that while not artful seems bluntly self-explanatory. Newspaper accounts usually refer to the organization as a gang-intervention program, and Hoddenbach and most of his colleagues are indeed former gang leaders. But CeaseFire doesn’t necessarily aim to get people out of gangs—nor interrupt the drug trade. It’s almost blindly focused on one thing: preventing shootings.» —“Blocking the Transmission of Violence” by Alex Kotlowitz New York Times May 4, 2008. (source: Double-Tongued Dictionary)