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ShotSpotter 101: The technology that could help Philly hear gunshots

July 20, 2015

When City Council gets back in session this September, expect the members to discuss ShotSpotter. Maybe you’ve heard of it. It’s a listening device that detects gunfire and reports to police so officers can investigate.

Jane Roh, director of communications for Council President Darrell Clarke, said while no date has been confirmed, the Public Safety Committee will likely schedule an information-gathering hearing this fall. In April, Council members already attended a demonstration from the Camden police about ShotSpotter. The likely forthcoming meeting is a sign that Philadelphia could be getting closer to getting ShotSpotter.

Why does Clarke want it? How does it work? And does it work well? Billy Penn explains this technology and its possible place in Philadelphia in ShotSpotter 101.
How did Philly become interested in ShotSpotter?

A few months ago, Clarke attended a gun violence prevention conference in Baltimore. He spoke about the safe passage of students to and from school in high-crime areas. David Chipman, senior vice president of public safety solutions at ShotSpotter, was speaking about the product. Chipman says Clarke invited him to Philadelphia so they could speak in greater depth about SpotShotter. In March, Clarke first proposed implementing a pilot program of ShotSpotter. Since then, not much has happened aside from the demonstration in Camden.
So I know it detects gunfire. How does that work?

A ShotSpotter system consists of about 15 to 20 small devices per square mile placed on buildings or street poles. The devices record sounds and send them back to a computer programmed with software to filter those sounds. When a sound resembling a gunshot is picked up, the file is sent within 30 seconds to acoustical experts at ShotSpotter’s headquarters in California. They work to verify if the sound was gunfire. If they do, they alert the necessary local police department, which can also view the soundwave.

Chipman says gunfire soundwaves travel farther than those of similar noises, like firecrackers or loud trucks, motorcycles and cars. Police dispatchers have said a gunshot wave usually looks like a sideways Christmas tree.