High-tech listening lets police crack down on 4th of July gunfire

In many American cities this Fourth of July, ShotSpotter hears and pinpoints each and every bang -- gunshots as well as illegal fireworks.

Eric Mack Contributing Editor
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Eric Mack
2 min read
ShotSpotter in use on patrol in Milwaukee. ShotSpotter

We're all excited that the United States of America is finally turning 237 years old this Fourth of July, but it's highly advisable that you keep your gun in your holster and all bullets out of the air when celebrating this week.

Celebratory Independence Day gunfire is a bad idea, and not just because of the potential of, you know, killing someone. This week, police departments in many cities are also armed -- with technology that can pinpoint the location of such well-meaning but ultimately dangerous gunshots.

ShotSpotter uses a system of sensors that listens across a wide area, such as a city, for gunshots and then triangulates the location of each shot fired and notifies local authorities that subscribe to the service.

ShotSpotter uses a combination of filters and human ears to distinguish between gunshots and the bang of fireworks on the Fourth of July. That means ShotSpotter has become something of a Swiss Army Knife for law enforcement to track not only celebratory gunfire but also the use of illegal fireworks around Independence Day.

Using ShotSpotter data from six law enforcement agencies in the San Francisco Bay Area, the company found that last year, 18 percent of July gunfire took place on July 4 and 5. The amount of celebratory gunfire heard around Independence Day is rivaled only by New Year's Eve and New Year's Day celebrations.


Last year, police in Birmingham, Ala., recorded more than 1,000 instances of gunfire on the Fourth using ShotSpotter and over 2,500 incidences of illegal fireworks in the city.

Police departments in ShotSpotter cities are putting extra officers on the streets to respond to reported violations, make arrests, and issue fines.

"We're going out, putting teams together, and using ShotSpotter to direct us to the right location and trying to arrest these people who are putting people's lives in danger," Captain Ersie A. Joyner of the Oakland Police Department told IDG. "These projectiles are very dangerous going up as well as going down."

Something tells me our founding fathers would have appreciated a sparkler more than flying bullets anyway. Have a happy and safe Fourth of July.