A gunshot detection system in Somerville

Somerville is re-evaluating the use of ShotSpotter, a surveillance system that detects sounds indicative of gunfire. The devices have drawn scrutiny locally after leaked internal data revealed disproportionately high use in minority communities.

Proponents of the technology say it saves lives and helps police catch criminals. Critics, including civil liberties advocates, raise concerns about the technology's accuracy and the risk of over-policing low-income or communities of color.

Boston Globe Reporter Spencer Buell joins The Common with more on the controversy behind the ShotSpotter gunshot detection system and its future in Somerville and beyond.