A network of sensors now dot a 4-square-mile area of north St. Louis County, touted by police as the latest way to crackdown on gun violence.
The tool, called ShotSpotter, sends officers an alert when it detects gunshots, and gives a more precise location than people could by calling 911. County officers will have to respond to those alerts, which could allow them to locate victims faster, talk to more witnesses or arrest a suspect sooner.
ShotSpotter’s deployment comes as news outlets’ investigations raise questions about how effective the tool is. But that’s not an issue for county Chief Jon Belmar.
“We’re very excited about ShotSpotter,” he said at a news conference Thursday in Jennings, one of the areas covered by the sensors. “This system enables our officers to know in real time where gunshots originate from and respond directly to the scene of the shooting. In fact, that has happened over the course of the last few days.”
The department turned on ShotSpotter on Monday. Since then, officers have received 18 notifications of shots fired and made one arrest. Officials would not say exactly where the microphones are located, but said they cover a span near Interstate 270 and West Florissant Avenue.
Twenty-one homicides have occurred this year in north St. Louis County, police said.
In Black Jack, which appears to be in ShotSpotter’s area, Lois Stevens said that officers rarely have to respond to gun calls.
“I think they should use something like that in those areas where we know there’s a lot of traffic and criminal activity and things,” Stevens said. “There’s a couple of gas stations on Natural Bridge, they always have things going on down there.”
Belmar said the department had come up with policies to make ShotSpotter as effective as possible.
Research published in 2016 by professors at Purdue University and the University of Virginia found that because people don’t call 911 if gunshots don’t lead to someone getting hurt or killed, ShotSpotter leads to more reports of gunfire. But an investigation by the public radio show Reveal found that more calls don’t lead to more arrests.
To Belmar, the most important element is a partnership with the social service agency Better Family Life. The department will let the organization know where gunshots are detected so that teams can go door-to-door in the neighborhood and offer help, according to James Clark, Better Family Life’s head of community outreach.
“We’re not doing police work,” Clark said. “We will do household assessments to see what individuals are in need of resources such as job training, GED training, drug treatment, and any other social service needs. We believe the best way to stop a bullet is with a job.”
The organization’s teams will also look for arguments that could turn violent in an effort to stop shots from being fired in the first place.
Precious Jones, a resident of Jennings, said she was glad ShotSpotter is in the area.
“We need it for our kids, women, everybody,” she said. “So many kids are dying, so many women are dying.”
Former Jennings police officer David Jennings said ShotSpotter would work best if it’s paired with other technology. For example, he said, alerts give officers a starting point to look for cameras, which could catch cars speeding in the neighborhoods.
“We know the speed limits are 15 to 20 miles per hour,” he said. “Anyone going over that is trying to get away from something. They’re not late for lunch."
Jerome Alexander, who also lives in Jennings, said he was worried about what would happen once people figure out where the sensors are located, saying that they’ll “figure out a way to manipulate it.”
The county is paying for ShotSpotter with a federal grant — for the first year. Money from the public safety sales tax increase approved in April would cover beyond that, should it be successful. Belmar defined success as a drop in the number of shots fired calls and shootings.
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