"It's not necessary an arrest tool, although that is the byproduct of it. We tend to tout it as a dispatch tool," Cataldo said.
Also, it took a while to get ShotSpotter operating effectively.
"When we first turned on the system we had rain in the area of Boston like we've never had. Torrential downpours," he said. The raging precipitation led to some false alarms, as did certain city buses, which run on compressed natural gas and have a distinctive, punchy backfire.
But after some months of fine-tuning, the system is now working well, Cataldo said.
Boston police are even in the process of integrating it with the municipal video-camera system -- a move that could put eyes, as well as ears, on shooting incidents.
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