Mayor Bill de Blasio's new city budget plan will include significant investment in ShotSpotter, a technology that acts as the eyes and ears of the NYPD, NBC 4 New York has learned exclusively.
The plan, being unveiled Thursday, involves another $3 million to cover 60 square miles of higher-crime neighborhoods across all five boroughs with ShotSpotter, which uses special sensors to detect the sound of shots fired.
That's double the area currently rigged with the technology, and a total of $5.5 million being invested.
Last year, ShotSpotter alerted police more than 1,600 times when someone fired a gun, according to the NYPD.
It also highlighted another phenomenon, however: in 3 of every 4 shootings captured by ShotSpotter, no witness picked up the phone to call 911.
"If people don't just call 911, we listen to the audio of some to these shots -- there can be multiple rounds of shots fired in very busy neighborhoods -- and we just don't get the 911 calls associated with them," said NYPD Deputy Commissioner Jessica Tisch.
Tisch noted that phenomenon isn't unique to New York City, and that a similar rate of failure to report occurs in other cities using ShotSpotter.
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In fact, the NYPD credits ShotSpotter in making eight arrests and 13 gun recoveries last year without using a single 911 call.
ShotSpotter works by triangulating the location of a gunshot to within 25 meters of where the shot was fired. The system then forwards a notification to an incident review center staffed by an operator trained to distinguish the sound of a gunshot, and then alert is sent to the NYPD.
De Blasio's office said crime is down 5.8 percent over the last two years and that the city is continuing to invest to drive it down further.
When ShotSpotter's pilot program was launched last year. authorities said the intention was to not only cut down on crime but to improve officer safety because precincts will have a better idea of how many officers to send to shootings.
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