Warren, Markey call for federal government to investigate ShotSpotter bostonglobe.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from bostonglobe.com Daily Mail and Mail on Sunday newspapers.
Proponents say ShotSpotter saves lives. Civil libertarians say the technology makes it more likely in communities of color that people will have tense or even dangerous run-ins with police.